Replace some ?ERR_* macros with ?ERRT_*

33 files changed, 375 insertions, 242 deletions

diff --git a/src/adhoc.erl b/src/adhoc.erl
index 788bf65ab..83a113a0c 100644
--- a/src/adhoc.erl
+++ b/src/adhoc.erl
@@ -68,7 +68,9 @@ parse_request(#iq{type = set, lang = Lang, sub_el = SubEl, xmlns = ?NS_COMMANDS}
         xdata     = XData,
         others    = Others
     };
-parse_request(_) -> {error, ?ERR_BAD_REQUEST}.
+parse_request(#iq{lang = Lang}) ->
+    Text = <<"Failed to parse ad-hoc command request">>,
+    {error, ?ERRT_BAD_REQUEST(Lang, Text)}.
 
 %% Borrowed from mod_vcard.erl
 find_xdata_el(#xmlel{children = SubEls}) ->
diff --git a/src/ejabberd_c2s.erl b/src/ejabberd_c2s.erl
index 936abc7a9..3736f7d07 100644
--- a/src/ejabberd_c2s.erl
+++ b/src/ejabberd_c2s.erl
@@ -619,8 +619,9 @@ wait_for_auth({xmlstreamelement, El}, StateData) ->
 	    send_element(StateData, Res),
 	    fsm_next_state(wait_for_auth, StateData);
 	{auth, _ID, set, {_U, _P, _D, <<"">>}} ->
-	    Err = jlib:make_error_reply(El,
-		    ?ERR_AUTH_NO_RESOURCE_PROVIDED((StateData#state.lang))),
+	    Lang = StateData#state.lang,
+	    Txt = <<"No resource provided">>,
+	    Err = jlib:make_error_reply(El, ?ERRT_NOT_ACCEPTABLE(Lang, Txt)),
 	    send_element(StateData, Err),
 	    fsm_next_state(wait_for_auth, StateData);
 	{auth, _ID, set, {U, P, D, R}} ->
@@ -685,7 +686,10 @@ wait_for_auth({xmlstreamelement, El}, StateData) ->
 			    ejabberd_hooks:run(c2s_auth_result, StateData#state.server,
 				[false, U, StateData#state.server,
 				    StateData#state.ip]),
-			    Err = jlib:make_error_reply(El, ?ERR_NOT_AUTHORIZED),
+			    Lang = StateData#state.lang,
+			    Txt = <<"Legacy authentication failed">>,
+			    Err = jlib:make_error_reply(
+				    El, ?ERRT_NOT_AUTHORIZED(Lang, Txt)),
 			    send_element(StateData, Err),
 			    fsm_next_state(wait_for_auth, StateData)
 		    end;
@@ -706,7 +710,9 @@ wait_for_auth({xmlstreamelement, El}, StateData) ->
 			    ejabberd_hooks:run(c2s_auth_result, StateData#state.server,
 				[false, U, StateData#state.server,
 				    StateData#state.ip]),
-			    Err = jlib:make_error_reply(El, ?ERR_NOT_ALLOWED),
+			    Lang = StateData#state.lang,
+			    Txt = <<"Legacy authentication forbidden">>,
+			    Err = jlib:make_error_reply(El, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 			    send_element(StateData, Err),
 			    fsm_next_state(wait_for_auth, StateData)
 		    end
@@ -1013,7 +1019,7 @@ wait_for_bind({xmlstreamelement, #xmlel{name = Name, attrs = Attrs} = El},
     end;
 wait_for_bind({xmlstreamelement, El}, StateData) ->
     case jlib:iq_query_info(El) of
-      #iq{type = set, xmlns = ?NS_BIND, sub_el = SubEl} =
+      #iq{type = set, lang = Lang, xmlns = ?NS_BIND, sub_el = SubEl} =
 	  IQ ->
 	  U = StateData#state.user,
 	  R1 = fxml:get_path_s(SubEl,
@@ -1025,7 +1031,8 @@ wait_for_bind({xmlstreamelement, El}, StateData) ->
 	      end,
 	  case R of
 	    error ->
-		Err = jlib:make_error_reply(El, ?ERR_BAD_REQUEST),
+		Txt = <<"Malformed resource">>,
+		Err = jlib:make_error_reply(El, ?ERRT_BAD_REQUEST(Lang, Txt)),
 		send_element(StateData, Err),
 		fsm_next_state(wait_for_bind, StateData);
 	    _ ->
@@ -1099,6 +1106,7 @@ open_session(StateData) ->
     U = StateData#state.user,
     R = StateData#state.resource,
     JID = StateData#state.jid,
+    Lang = StateData#state.lang,
     case acl:match_rule(StateData#state.server,
                         StateData#state.access, JID) of
         allow ->
@@ -1136,7 +1144,8 @@ open_session(StateData) ->
                                StateData#state.server, [JID]),
             ?INFO_MSG("(~w) Forbidden session for ~s",
                       [StateData#state.socket, jid:to_string(JID)]),
-            {error, ?ERR_NOT_ALLOWED}
+	    Txt = <<"Denied by ACL">>,
+            {error, ?ERRT_NOT_ALLOWED(Lang, Txt)}
     end.
 
 session_established({xmlstreamelement, #xmlel{name = Name} = El}, StateData)
@@ -2275,30 +2284,32 @@ get_priority_from_presence(PresencePacket) ->
     end.
 
 process_privacy_iq(From, To,
-		   #iq{type = Type, sub_el = SubEl} = IQ, StateData) ->
-    {Res, NewStateData} = case Type of
-			    get ->
-				R = ejabberd_hooks:run_fold(privacy_iq_get,
-							    StateData#state.server,
-							    {error,
-							     ?ERR_FEATURE_NOT_IMPLEMENTED},
-							    [From, To, IQ,
-							     StateData#state.privacy_list]),
-				{R, StateData};
-			    set ->
-				case ejabberd_hooks:run_fold(privacy_iq_set,
-							     StateData#state.server,
-							     {error,
-							      ?ERR_FEATURE_NOT_IMPLEMENTED},
-							     [From, To, IQ])
-				    of
-				  {result, R, NewPrivList} ->
-				      {{result, R},
-				       StateData#state{privacy_list =
-							   NewPrivList}};
-				  R -> {R, StateData}
-				end
-			  end,
+		   #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ, StateData) ->
+    Txt = <<"No module is handling this query">>,
+    {Res, NewStateData} =
+	case Type of
+	    get ->
+		R = ejabberd_hooks:run_fold(
+		      privacy_iq_get,
+		      StateData#state.server,
+		      {error, ?ERRT_FEATURE_NOT_IMPLEMENTED(Lang, Txt)},
+		      [From, To, IQ,
+		       StateData#state.privacy_list]),
+		{R, StateData};
+	    set ->
+		case ejabberd_hooks:run_fold(
+		       privacy_iq_set,
+		       StateData#state.server,
+		       {error, ?ERRT_FEATURE_NOT_IMPLEMENTED(Lang, Txt)},
+		       [From, To, IQ])
+		of
+		    {result, R, NewPrivList} ->
+			{{result, R},
+			 StateData#state{privacy_list =
+					     NewPrivList}};
+		    R -> {R, StateData}
+		end
+	end,
     IQRes = case Res of
 	      {result, Result} ->
 		  IQ#iq{type = result, sub_el = Result};
@@ -2365,15 +2376,16 @@ process_unauthenticated_stanza(StateData, El) ->
 	      _ -> El
 	    end,
     case jlib:iq_query_info(NewEl) of
-      #iq{} = IQ ->
+      #iq{lang = L} = IQ ->
 	  Res = ejabberd_hooks:run_fold(c2s_unauthenticated_iq,
 					StateData#state.server, empty,
 					[StateData#state.server, IQ,
 					 StateData#state.ip]),
 	  case Res of
 	    empty ->
+		Txt = <<"Authentication required">>,
 		ResIQ = IQ#iq{type = error,
-			      sub_el = [?ERR_SERVICE_UNAVAILABLE]},
+			      sub_el = [?ERRT_SERVICE_UNAVAILABLE(L, Txt)]},
 		Res1 = jlib:replace_from_to(jid:make(<<"">>,
 							  StateData#state.server,
 							  <<"">>),
@@ -2879,6 +2891,7 @@ handle_unacked_stanzas(StateData)
 		    false
 	      end
 	end,
+    Lang = StateData#state.lang,
     ReRoute = case ResendOnTimeout of
 		true ->
 		    fun(From, To, El, Time) ->
@@ -2887,9 +2900,11 @@ handle_unacked_stanzas(StateData)
 		    end;
 		false ->
 		    fun(From, To, El, _Time) ->
+			    Txt = <<"User session not found">>,
 			    Err =
-				jlib:make_error_reply(El,
-						      ?ERR_SERVICE_UNAVAILABLE),
+				jlib:make_error_reply(
+				  El,
+				  ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)),
 			    ejabberd_router:route(To, From, Err)
 		    end
 	      end,
@@ -2897,7 +2912,9 @@ handle_unacked_stanzas(StateData)
 		?DEBUG("Dropping presence stanza from ~s",
 		       [jid:to_string(From)]);
 	   (From, To, #xmlel{name = <<"iq">>} = El, _Time) ->
-		Err = jlib:make_error_reply(El, ?ERR_SERVICE_UNAVAILABLE),
+		Txt = <<"User session not found">>,
+		Err = jlib:make_error_reply(
+			El, ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)),
 		ejabberd_router:route(To, From, Err);
 	   (From, To, El, Time) ->
 		%% We'll drop the stanza if it was <forwarded/> by some
diff --git a/src/ejabberd_local.erl b/src/ejabberd_local.erl
index 7c30f3b6c..5566073e9 100644
--- a/src/ejabberd_local.erl
+++ b/src/ejabberd_local.erl
@@ -74,7 +74,7 @@ start_link() ->
 process_iq(From, To, Packet) ->
     IQ = jlib:iq_query_info(Packet),
     case IQ of
-      #iq{xmlns = XMLNS} ->
+      #iq{xmlns = XMLNS, lang = Lang} ->
 	  Host = To#jid.lserver,
 	  case ets:lookup(?IQTABLE, {XMLNS, Host}) of
 	    [{_, Module, Function}] ->
@@ -87,8 +87,10 @@ process_iq(From, To, Packet) ->
 		gen_iq_handler:handle(Host, Module, Function, Opts,
 				      From, To, IQ);
 	    [] ->
-		Err = jlib:make_error_reply(Packet,
-					    ?ERR_FEATURE_NOT_IMPLEMENTED),
+		Txt = <<"No module is handling this query">>,
+		Err = jlib:make_error_reply(
+			Packet,
+			?ERRT_FEATURE_NOT_IMPLEMENTED(Lang, Txt)),
 		ejabberd_router:route(To, From, Err)
 	  end;
       reply ->
@@ -166,8 +168,10 @@ refresh_iq_handlers() ->
     ejabberd_local ! refresh_iq_handlers.
 
 bounce_resource_packet(From, To, Packet) ->
+    Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet),
+    Txt = <<"No available resource found">>,
     Err = jlib:make_error_reply(Packet,
-				?ERR_ITEM_NOT_FOUND),
+				?ERRT_ITEM_NOT_FOUND(Lang, Txt)),
     ejabberd_router:route(To, From, Err),
     stop.
 
diff --git a/src/ejabberd_s2s.erl b/src/ejabberd_s2s.erl
index 0eab46337..be1ee4659 100644
--- a/src/ejabberd_s2s.erl
+++ b/src/ejabberd_s2s.erl
@@ -312,8 +312,10 @@ do_route(From, To, Packet) ->
 	    <<"error">> -> ok;
 	    <<"result">> -> ok;
 	    _ ->
-		Err = jlib:make_error_reply(Packet,
-					    ?ERR_SERVICE_UNAVAILABLE),
+		Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet),
+		Txt = <<"No s2s connection found">>,
+		Err = jlib:make_error_reply(
+			Packet, ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)),
 		ejabberd_router:route(To, From, Err)
 	  end,
 	  false
diff --git a/src/ejabberd_service.erl b/src/ejabberd_service.erl
index 5caae6102..465fb587a 100644
--- a/src/ejabberd_service.erl
+++ b/src/ejabberd_service.erl
@@ -280,7 +280,9 @@ stream_established({xmlstreamelement, El}, StateData) ->
 	 and (FromJID /= error) ->
 	   ejabberd_router:route(FromJID, ToJID, NewEl);
        true ->
-	   Err = jlib:make_error_reply(NewEl, ?ERR_BAD_REQUEST),
+	   Lang = fxml:get_tag_attr_s(<<"xml:lang">>, El),
+	   Txt = <<"Incorrect stanza name or from/to JID">>,
+	   Err = jlib:make_error_reply(NewEl, ?ERRT_BAD_REQUEST(Lang, Txt)),
 	   send_element(StateData, Err),
 	   error
     end,
@@ -360,7 +362,9 @@ handle_info({route, From, To, Packet}, StateName,
 					      attrs = Attrs2, children = Els}),
 	  send_text(StateData, Text);
       deny ->
-	  Err = jlib:make_error_reply(Packet, ?ERR_NOT_ALLOWED),
+	  Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet),
+	  Txt = <<"Denied by ACL">>,
+	  Err = jlib:make_error_reply(Packet, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 	  ejabberd_router:route_error(To, From, Err, Packet)
     end,
     {next_state, StateName, StateData};
diff --git a/src/ejabberd_sm.erl b/src/ejabberd_sm.erl
index 218e657f3..4f7cfeeaa 100644
--- a/src/ejabberd_sm.erl
+++ b/src/ejabberd_sm.erl
@@ -159,8 +159,10 @@ check_in_subscription(Acc, User, Server, _JID, _Type, _Reason) ->
 -spec bounce_offline_message(jid(), jid(), xmlel()) -> stop.
 
 bounce_offline_message(From, To, Packet) ->
-    Err = jlib:make_error_reply(Packet,
-				?ERR_SERVICE_UNAVAILABLE),
+    Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet),
+    Txt = <<"User session not found">>,
+    Err = jlib:make_error_reply(
+	    Packet, ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)),
     ejabberd_router:route(To, From, Err),
     stop.
 
@@ -423,6 +425,7 @@ do_route(From, To, #xmlel{} = Packet) ->
     #jid{user = User, server = Server,
 	 luser = LUser, lserver = LServer, lresource = LResource} = To,
     #xmlel{name = Name, attrs = Attrs} = Packet,
+    Lang = fxml:get_attr_s(<<"xml:lang">>, Attrs),
     case LResource of
       <<"">> ->
 	  case Name of
@@ -496,8 +499,9 @@ do_route(From, To, #xmlel{} = Packet) ->
 		  <<"headline">> -> route_message(From, To, Packet, headline);
 		  <<"error">> -> ok;
 		  <<"groupchat">> ->
-		      Err = jlib:make_error_reply(Packet,
-						  ?ERR_SERVICE_UNAVAILABLE),
+		      ErrTxt = <<"Incorrect message type">>,
+		      Err = jlib:make_error_reply(
+			      Packet, ?ERRT_SERVICE_UNAVAILABLE(Lang, ErrTxt)),
 		      ejabberd_router:route(To, From, Err);
 		  _ ->
 		      route_message(From, To, Packet, normal)
@@ -517,8 +521,10 @@ do_route(From, To, #xmlel{} = Packet) ->
 			<<"">> -> route_message(From, To, Packet, normal);
 			<<"error">> -> ok;
 			_ ->
-			    Err = jlib:make_error_reply(Packet,
-							?ERR_SERVICE_UNAVAILABLE),
+			    ErrTxt = <<"Incorrect message type">>,
+			    Err = jlib:make_error_reply(
+				    Packet,
+				    ?ERRT_SERVICE_UNAVAILABLE(Lang, ErrTxt)),
 			    ejabberd_router:route(To, From, Err)
 		      end;
 		  <<"iq">> ->
@@ -526,8 +532,10 @@ do_route(From, To, #xmlel{} = Packet) ->
 			<<"error">> -> ok;
 			<<"result">> -> ok;
 			_ ->
-			    Err = jlib:make_error_reply(Packet,
-							?ERR_SERVICE_UNAVAILABLE),
+			    ErrTxt = <<"User session not found">>,
+			    Err = jlib:make_error_reply(
+				    Packet,
+				    ?ERRT_SERVICE_UNAVAILABLE(Lang, ErrTxt)),
 			    ejabberd_router:route(To, From, Err)
 		      end;
 		  _ -> ?DEBUG("packet dropped~n", [])
@@ -684,7 +692,7 @@ get_max_user_sessions(LUser, Host) ->
 process_iq(From, To, Packet) ->
     IQ = jlib:iq_query_info(Packet),
     case IQ of
-      #iq{xmlns = XMLNS} ->
+      #iq{xmlns = XMLNS, lang = Lang} ->
 	  Host = To#jid.lserver,
 	  case ets:lookup(sm_iqtable, {XMLNS, Host}) of
 	    [{_, Module, Function}] ->
@@ -697,8 +705,10 @@ process_iq(From, To, Packet) ->
 		gen_iq_handler:handle(Host, Module, Function, Opts,
 				      From, To, IQ);
 	    [] ->
-		Err = jlib:make_error_reply(Packet,
-					    ?ERR_SERVICE_UNAVAILABLE),
+		Txt = <<"No module is handling this query">>,
+		Err = jlib:make_error_reply(
+			Packet,
+			?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)),
 		ejabberd_router:route(To, From, Err)
 	  end;
       reply -> ok;
diff --git a/src/mod_adhoc.erl b/src/mod_adhoc.erl
index 9947c84ac..9e0682f7d 100644
--- a/src/mod_adhoc.erl
+++ b/src/mod_adhoc.erl
@@ -233,7 +233,7 @@ process_sm_iq(From, To, IQ) ->
     process_adhoc_request(From, To, IQ, adhoc_sm_commands).
 
 process_adhoc_request(From, To,
-		      #iq{sub_el = SubEl} = IQ, Hook) ->
+		      #iq{sub_el = SubEl, lang = Lang} = IQ, Hook) ->
     ?DEBUG("About to parse ~p...", [IQ]),
     case adhoc:parse_request(IQ) of
       {error, Error} ->
@@ -245,8 +245,9 @@ process_adhoc_request(From, To,
 	      of
 	    ignore -> ignore;
 	    empty ->
+		Txt = <<"No hook has processed this command">>,
 		IQ#iq{type = error,
-		      sub_el = [SubEl, ?ERR_ITEM_NOT_FOUND]};
+		      sub_el = [SubEl, ?ERRT_ITEM_NOT_FOUND(Lang, Txt)]};
 	    {error, Error} ->
 		IQ#iq{type = error, sub_el = [SubEl, Error]};
 	    Command -> IQ#iq{type = result, sub_el = [Command]}
@@ -277,7 +278,9 @@ ping_command(_Acc, _From, _To,
 						      [{<<"info">>,
 							translate:translate(Lang,
 									    <<"Pong">>)}]});
-       true -> {error, ?ERR_BAD_REQUEST}
+       true ->
+	    Txt = <<"Incorrect value of 'action' attribute">>,
+	    {error, ?ERRT_BAD_REQUEST(Lang, Txt)}
     end;
 ping_command(Acc, _From, _To, _Request) -> Acc.
 
diff --git a/src/mod_blocking.erl b/src/mod_blocking.erl
index 815884ff2..d94b3090f 100644
--- a/src/mod_blocking.erl
+++ b/src/mod_blocking.erl
@@ -64,29 +64,33 @@ process_iq(_From, _To, IQ) ->
     IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]}.
 
 process_iq_get(_, From, _To,
-	       #iq{xmlns = ?NS_BLOCKING,
+	       #iq{xmlns = ?NS_BLOCKING, lang = Lang,
 		   sub_el = #xmlel{name = <<"blocklist">>}},
 	       _) ->
     #jid{luser = LUser, lserver = LServer} = From,
-    {stop, process_blocklist_get(LUser, LServer)};
+    {stop, process_blocklist_get(LUser, LServer, Lang)};
 process_iq_get(Acc, _, _, _, _) -> Acc.
 
 process_iq_set(_, From, _To,
-	       #iq{xmlns = ?NS_BLOCKING,
+	       #iq{xmlns = ?NS_BLOCKING, lang = Lang,
 		   sub_el =
 		       #xmlel{name = SubElName, children = SubEls}}) ->
     #jid{luser = LUser, lserver = LServer} = From,
     Res = case {SubElName, fxml:remove_cdata(SubEls)} of
-	    {<<"block">>, []} -> {error, ?ERR_BAD_REQUEST};
+	    {<<"block">>, []} ->
+		Txt = <<"No items found in this query">>,
+		{error, ?ERRT_BAD_REQUEST(Lang, Txt)};
 	    {<<"block">>, Els} ->
 		JIDs = parse_blocklist_items(Els, []),
-		process_blocklist_block(LUser, LServer, JIDs);
+		process_blocklist_block(LUser, LServer, JIDs, Lang);
 	    {<<"unblock">>, []} ->
-		process_blocklist_unblock_all(LUser, LServer);
+		process_blocklist_unblock_all(LUser, LServer, Lang);
 	    {<<"unblock">>, Els} ->
 		JIDs = parse_blocklist_items(Els, []),
-		process_blocklist_unblock(LUser, LServer, JIDs);
-	    _ -> {error, ?ERR_BAD_REQUEST}
+		process_blocklist_unblock(LUser, LServer, JIDs, Lang);
+	    _ ->
+		Txt = <<"Unknown blocking command">>,
+		{error, ?ERRT_BAD_REQUEST(Lang, Txt)}
 	  end,
     {stop, Res};
 process_iq_set(Acc, _, _, _) -> Acc.
@@ -125,7 +129,7 @@ parse_blocklist_items([#xmlel{name = <<"item">>,
 parse_blocklist_items([_ | Els], JIDs) ->
     parse_blocklist_items(Els, JIDs).
 
-process_blocklist_block(LUser, LServer, JIDs) ->
+process_blocklist_block(LUser, LServer, JIDs, Lang) ->
     Filter = fun (List) ->
 		     AlreadyBlocked = list_to_blocklist_jids(List, []),
 		     lists:foldr(fun (JID, List1) ->
@@ -143,8 +147,8 @@ process_blocklist_block(LUser, LServer, JIDs) ->
 				 end,
 				 List, JIDs)
 	     end,
-    case process_blocklist_block(LUser, LServer, Filter,
-				 gen_mod:db_type(LServer, mod_privacy))
+    case process_blocklist_block_db(LUser, LServer, Filter,
+				    gen_mod:db_type(LServer, mod_privacy))
 	of
       {atomic, {ok, Default, List}} ->
 	  UserList = make_userlist(Default, List),
@@ -155,11 +159,11 @@ process_blocklist_block(LUser, LServer, JIDs) ->
 	  {result, [], UserList};
       _Err ->
 	    ?ERROR_MSG("Error processing ~p: ~p", [{LUser, LServer, JIDs}, _Err]),
-	    {error, ?ERR_INTERNAL_SERVER_ERROR}
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, <<"Database failure">>)}
     end.
 
-process_blocklist_block(LUser, LServer, Filter,
-			mnesia) ->
+process_blocklist_block_db(LUser, LServer, Filter,
+			   mnesia) ->
     F = fun () ->
 		case mnesia:wread({privacy, {LUser, LServer}}) of
 		  [] ->
@@ -185,8 +189,8 @@ process_blocklist_block(LUser, LServer, Filter,
 		{ok, NewDefault, NewList}
 	end,
     mnesia:transaction(F);
-process_blocklist_block(LUser, LServer, Filter,
-			riak) ->
+process_blocklist_block_db(LUser, LServer, Filter,
+			   riak) ->
     {atomic,
      begin
          case ejabberd_riak:get(privacy, mod_privacy:privacy_schema(),
@@ -218,7 +222,7 @@ process_blocklist_block(LUser, LServer, Filter,
                  Err
          end
      end};
-process_blocklist_block(LUser, LServer, Filter, odbc) ->
+process_blocklist_block_db(LUser, LServer, Filter, odbc) ->
     F = fun () ->
 		Default = case
 			    mod_privacy:sql_get_default_privacy_list_t(LUser)
@@ -246,7 +250,7 @@ process_blocklist_block(LUser, LServer, Filter, odbc) ->
 	end,
     ejabberd_odbc:sql_transaction(LServer, F).
 
-process_blocklist_unblock_all(LUser, LServer) ->
+process_blocklist_unblock_all(LUser, LServer, Lang) ->
     Filter = fun (List) ->
 		     lists:filter(fun (#listitem{action = A}) -> A =/= deny
 				  end,
@@ -263,10 +267,10 @@ process_blocklist_unblock_all(LUser, LServer) ->
 	  {result, [], UserList};
       _Err ->
 	    ?ERROR_MSG("Error processing ~p: ~p", [{LUser, LServer}, _Err]),
-	    {error, ?ERR_INTERNAL_SERVER_ERROR}
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, <<"Database failure">>)}
     end.
 
-process_blocklist_unblock(LUser, LServer, JIDs) ->
+process_blocklist_unblock(LUser, LServer, JIDs, Lang) ->
     Filter = fun (List) ->
 		     lists:filter(fun (#listitem{action = deny, type = jid,
 						 value = JID}) ->
@@ -287,7 +291,7 @@ process_blocklist_unblock(LUser, LServer, JIDs) ->
 	  {result, [], UserList};
       _Err ->
 	    ?ERROR_MSG("Error processing ~p: ~p", [{LUser, LServer, JIDs}, _Err]),
-	    {error, ?ERR_INTERNAL_SERVER_ERROR}
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, <<"Database failure">>)}
     end.
 
 unblock_by_filter(LUser, LServer, Filter, mnesia) ->
@@ -375,11 +379,12 @@ broadcast_blocklist_event(LUser, LServer, Event) ->
     ejabberd_sm:route(JID, JID,
                       {broadcast, {blocking, Event}}).
 
-process_blocklist_get(LUser, LServer) ->
-    case process_blocklist_get(LUser, LServer,
-			       gen_mod:db_type(LServer, mod_privacy))
+process_blocklist_get(LUser, LServer, Lang) ->
+    case process_blocklist_get_db(LUser, LServer,
+				  gen_mod:db_type(LServer, mod_privacy))
 	of
-      error -> {error, ?ERR_INTERNAL_SERVER_ERROR};
+      error ->
+	  {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, <<"Database failure">>)};
       List ->
 	  JIDs = list_to_blocklist_jids(List, []),
 	  Items = lists:map(fun (JID) ->
@@ -397,7 +402,7 @@ process_blocklist_get(LUser, LServer) ->
 		   children = Items}]}
     end.
 
-process_blocklist_get(LUser, LServer, mnesia) ->
+process_blocklist_get_db(LUser, LServer, mnesia) ->
     case catch mnesia:dirty_read(privacy, {LUser, LServer})
 	of
       {'EXIT', _Reason} -> error;
@@ -408,7 +413,7 @@ process_blocklist_get(LUser, LServer, mnesia) ->
 	    _ -> []
 	  end
     end;
-process_blocklist_get(LUser, LServer, riak) ->
+process_blocklist_get_db(LUser, LServer, riak) ->
     case ejabberd_riak:get(privacy, mod_privacy:privacy_schema(),
 			   {LUser, LServer}) of
         {ok, #privacy{default = Default, lists = Lists}} ->
@@ -421,7 +426,7 @@ process_blocklist_get(LUser, LServer, riak) ->
         {error, _} ->
             error
     end;
-process_blocklist_get(LUser, LServer, odbc) ->
+process_blocklist_get_db(LUser, LServer, odbc) ->
     case catch
 	   mod_privacy:sql_get_default_privacy_list(LUser, LServer)
 	of
diff --git a/src/mod_carboncopy.erl b/src/mod_carboncopy.erl
index 81cf78a9d..1e0499eec 100644
--- a/src/mod_carboncopy.erl
+++ b/src/mod_carboncopy.erl
@@ -102,7 +102,9 @@ iq_handler2(From, To, IQ) ->
 iq_handler1(From, To, IQ) ->
 	iq_handler(From, To, IQ, ?NS_CARBONS_1).
 
-iq_handler(From, _To,  #iq{type=set, sub_el = #xmlel{name = Operation, children = []}} = IQ, CC)->
+iq_handler(From, _To,
+	   #iq{type=set, lang = Lang,
+	       sub_el = #xmlel{name = Operation} = SubEl} = IQ, CC)->
     ?DEBUG("carbons IQ received: ~p", [IQ]),
     {U, S, R} = jid:tolower(From),
     Result = case Operation of
@@ -118,12 +120,14 @@ iq_handler(From, _To,  #iq{type=set, sub_el = #xmlel{name = Operation, children
 	    ?DEBUG("carbons IQ result: ok", []),
             IQ#iq{type=result, sub_el=[]};
 	{error,_Error} ->
-	    ?WARNING_MSG("Error enabling / disabling carbons: ~p", [Result]),
-            IQ#iq{type=error,sub_el = [?ERR_BAD_REQUEST]}
+	    ?ERROR_MSG("Error enabling / disabling carbons: ~p", [Result]),
+	    Txt = <<"Database failure">>,
+            IQ#iq{type=error,sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]}
     end;
 
-iq_handler(_From, _To, IQ, _CC)->
-    IQ#iq{type=error, sub_el = [?ERR_NOT_ALLOWED]}.
+iq_handler(_From, _To, #iq{lang = Lang, sub_el = SubEl} = IQ, _CC)->
+    Txt = <<"Value 'get' of 'type' attribute is not allowed">>,
+    IQ#iq{type=error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]}.
 
 user_send_packet(Packet, _C2SState, From, To) ->
     check_and_forward(From, To, Packet, sent).
diff --git a/src/mod_configure2.erl b/src/mod_configure2.erl
index 0acd4a78c..a8287b4d4 100644
--- a/src/mod_configure2.erl
+++ b/src/mod_configure2.erl
@@ -56,15 +56,17 @@ stop(Host) ->
 				     ?NS_ECONFIGURE).
 
 process_local_iq(From, To,
-		 #iq{type = Type, lang = _Lang, sub_el = SubEl} = IQ) ->
+		 #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case acl:match_rule(To#jid.lserver, configure, From) of
       deny ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Denied by ACL">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       allow ->
 	  case Type of
 	    set ->
+		Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
 		IQ#iq{type = error,
-		      sub_el = [SubEl, ?ERR_FEATURE_NOT_IMPLEMENTED]};
+		      sub_el = [SubEl, ?ERRT_FEATURE_NOT_IMPLEMENTED(Lang, Txt)]};
 	    %%case fxml:get_tag_attr_s("type", SubEl) of
 	    %%    "cancel" ->
 	    %%        IQ#iq{type = result,
@@ -98,7 +100,7 @@ process_local_iq(From, To,
 	    %%		   sub_el = [SubEl, ?ERR_NOT_ALLOWED]}
 	    %%end;
 	    get ->
-		case process_get(SubEl) of
+		case process_get(SubEl, Lang) of
 		  {result, Res} -> IQ#iq{type = result, sub_el = [Res]};
 		  {error, Error} ->
 		      IQ#iq{type = error, sub_el = [SubEl, Error]}
@@ -106,7 +108,7 @@ process_local_iq(From, To,
 	  end
     end.
 
-process_get(#xmlel{name = <<"info">>}) ->
+process_get(#xmlel{name = <<"info">>}, _Lang) ->
     S2SConns = ejabberd_s2s:dirty_get_connections(),
     TConns = lists:usort([element(2, C) || C <- S2SConns]),
     Attrs = [{<<"registered-users">>,
@@ -130,7 +132,7 @@ process_get(#xmlel{name = <<"info">>}) ->
 	    attrs = [{<<"xmlns">>, ?NS_ECONFIGURE} | Attrs],
 	    children = []}};
 process_get(#xmlel{name = <<"welcome-message">>,
-		   attrs = Attrs}) ->
+		   attrs = Attrs}, _Lang) ->
     {Subj, Body} = ejabberd_config:get_option(
                      welcome_message,
                      fun({Subj, Body}) ->
@@ -146,7 +148,7 @@ process_get(#xmlel{name = <<"welcome-message">>,
 		 #xmlel{name = <<"body">>, attrs = [],
 			children = [{xmlcdata, Body}]}]}};
 process_get(#xmlel{name = <<"registration-watchers">>,
-		   attrs = Attrs}) ->
+		   attrs = Attrs}, _Lang) ->
     SubEls = ejabberd_config:get_option(
                registration_watchers,
                fun(JIDs) when is_list(JIDs) ->
@@ -160,14 +162,14 @@ process_get(#xmlel{name = <<"registration-watchers">>,
     {result,
      #xmlel{name = <<"registration_watchers">>,
 	    attrs = Attrs, children = SubEls}};
-process_get(#xmlel{name = <<"acls">>, attrs = Attrs}) ->
+process_get(#xmlel{name = <<"acls">>, attrs = Attrs}, _Lang) ->
     Str = iolist_to_binary(io_lib:format("~p.",
 					 [ets:tab2list(acl)])),
     {result,
      #xmlel{name = <<"acls">>, attrs = Attrs,
 	    children = [{xmlcdata, Str}]}};
 process_get(#xmlel{name = <<"access">>,
-		   attrs = Attrs}) ->
+		   attrs = Attrs}, _Lang) ->
     Str = iolist_to_binary(io_lib:format("~p.",
 					 [ets:select(local_config,
 						     [{{local_config, {access, '$1'},
@@ -178,13 +180,14 @@ process_get(#xmlel{name = <<"access">>,
     {result,
      #xmlel{name = <<"access">>, attrs = Attrs,
 	    children = [{xmlcdata, Str}]}};
-process_get(#xmlel{name = <<"last">>, attrs = Attrs}) ->
+process_get(#xmlel{name = <<"last">>, attrs = Attrs}, Lang) ->
     case catch mnesia:dirty_select(last_activity,
 				   [{{last_activity, '_', '$1', '_'}, [],
 				     ['$1']}])
 	of
       {'EXIT', _Reason} ->
-	  {error, ?ERR_INTERNAL_SERVER_ERROR};
+	  Txt = <<"Database failure">>,
+	  {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)};
       Vals ->
 	  TimeStamp = p1_time_compat:system_time(seconds),
 	  Str = list_to_binary(
@@ -196,7 +199,7 @@ process_get(#xmlel{name = <<"last">>, attrs = Attrs}) ->
     end;
 %%process_get({xmlelement, Name, Attrs, SubEls}) ->
 %%    {result, };
-process_get(_) -> {error, ?ERR_BAD_REQUEST}.
+process_get(_, _) -> {error, ?ERR_BAD_REQUEST}.
 
 mod_opt_type(iqdisc) -> fun gen_iq_handler:check_type/1;
 mod_opt_type(_) -> [iqdisc].
diff --git a/src/mod_echo.erl b/src/mod_echo.erl
index 7184ee4e7..7d9f81f82 100644
--- a/src/mod_echo.erl
+++ b/src/mod_echo.erl
@@ -118,7 +118,10 @@ handle_cast(_Msg, State) -> {noreply, State}.
 handle_info({route, From, To, Packet}, State) ->
     Packet2 = case From#jid.user of
 		<<"">> ->
-		    jlib:make_error_reply(Packet, ?ERR_BAD_REQUEST);
+		    Lang = fxml:get_tag_attr_s(<<"xml:lang">>, Packet),
+		    Txt = <<"User part of JID in 'from' is empty">>,
+		    jlib:make_error_reply(
+		      Packet, ?ERRT_BAD_REQUEST(Lang, Txt));
 		_ -> Packet
 	      end,
     do_client_version(disabled, To, From),
diff --git a/src/mod_http_upload.erl b/src/mod_http_upload.erl
index 6c029c437..214badca5 100644
--- a/src/mod_http_upload.erl
+++ b/src/mod_http_upload.erl
@@ -569,7 +569,8 @@ process_iq(From,
 	deny ->
 	    ?DEBUG("Denying HTTP upload slot request from ~s",
 		   [jid:to_string(From)]),
-	    IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}
+	    Txt = <<"Denied by ACL">>,
+	    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}
     end;
 process_iq(_From, #iq{sub_el = SubEl} = IQ, _State) ->
     IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
@@ -601,7 +602,8 @@ parse_request(#xmlel{name = <<"request">>, attrs = Attrs} = Request, Lang) ->
 		    {error, ?ERRT_BAD_REQUEST(Lang, Text)}
 	    end;
 	_ ->
-	    {error, ?ERR_BAD_REQUEST}
+	    Text = <<"No or invalid XML namespace">>,
+	    {error, ?ERRT_BAD_REQUEST(Lang, Text)}
     end;
 parse_request(_El, _Lang) -> {error, ?ERR_BAD_REQUEST}.
 
@@ -639,7 +641,7 @@ create_slot(#state{service_url = undefined,
     end;
 create_slot(#state{service_url = ServiceURL},
 	    #jid{luser = U, lserver = S} = JID, File, Size, ContentType,
-	    _Lang) ->
+	    Lang) ->
     Options = [{body_format, binary}, {full_result, false}],
     HttpOptions = [{timeout, ?SERVICE_REQUEST_TIMEOUT}],
     SizeStr = jlib:integer_to_binary(Size),
@@ -659,7 +661,8 @@ create_slot(#state{service_url = ServiceURL},
 		Lines ->
 		    ?ERROR_MSG("Can't parse data received for ~s from <~s>: ~p",
 			       [jid:to_string(JID), ServiceURL, Lines]),
-		    {error, ?ERR_SERVICE_UNAVAILABLE}
+		    Txt = <<"Failed to parse HTTP response">>,
+		    {error, ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)}
 	    end;
 	{ok, {402, _Body}} ->
 	    ?INFO_MSG("Got status code 402 for ~s from <~s>",
diff --git a/src/mod_last.erl b/src/mod_last.erl
index 33f88e020..e67a02cc2 100644
--- a/src/mod_last.erl
+++ b/src/mod_last.erl
@@ -86,10 +86,11 @@ stop(Host) ->
 %%%
 
 process_local_iq(_From, _To,
-		 #iq{type = Type, sub_el = SubEl} = IQ) ->
+		 #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  Sec = get_node_uptime(),
 	  IQ#iq{type = result,
@@ -123,10 +124,11 @@ now_to_seconds({MegaSecs, Secs, _MicroSecs}) ->
 %%%
 
 process_sm_iq(From, To,
-	      #iq{type = Type, sub_el = SubEl} = IQ) ->
+	      #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  User = To#jid.luser,
 	  Server = To#jid.lserver,
@@ -150,10 +152,12 @@ process_sm_iq(From, To,
 		     of
 		   allow -> get_last_iq(IQ, SubEl, User, Server);
 		   deny ->
-		       IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}
+		       Txt = <<"Denied by privacy lists">>,
+		       IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}
 		 end;
 	     true ->
-		 IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}
+		 Txt = <<"Not subscribed">>,
+		 IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}
 	  end
     end.
 
@@ -193,16 +197,18 @@ get_last(LUser, LServer, odbc) ->
         Reason -> {error, {invalid_result, Reason}}
     end.
 
-get_last_iq(IQ, SubEl, LUser, LServer) ->
+get_last_iq(#iq{lang = Lang} = IQ, SubEl, LUser, LServer) ->
     case ejabberd_sm:get_user_resources(LUser, LServer) of
       [] ->
 	  case get_last(LUser, LServer) of
 	    {error, _Reason} ->
+		Txt = <<"Database failure">>,
 		IQ#iq{type = error,
-		      sub_el = [SubEl, ?ERR_INTERNAL_SERVER_ERROR]};
+		      sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]};
 	    not_found ->
+		Txt = <<"No info about last activity found">>,
 		IQ#iq{type = error,
-		      sub_el = [SubEl, ?ERR_SERVICE_UNAVAILABLE]};
+		      sub_el = [SubEl, ?ERRT_SERVICE_UNAVAILABLE(Lang, Txt)]};
 	    {ok, TimeStamp, Status} ->
 		TimeStamp2 = p1_time_compat:system_time(seconds),
 		Sec = TimeStamp2 - TimeStamp,
diff --git a/src/mod_mam.erl b/src/mod_mam.erl
index d212f63c6..862adee99 100644
--- a/src/mod_mam.erl
+++ b/src/mod_mam.erl
@@ -447,7 +447,7 @@ process_iq(LServer, #iq{sub_el = #xmlel{attrs = Attrs}} = IQ) ->
 % Preference setting (both v0.2 & v0.3)
 process_iq(#jid{luser = LUser, lserver = LServer},
 	   #jid{lserver = LServer},
-	   #iq{type = set, sub_el = #xmlel{name = <<"prefs">>} = SubEl} = IQ) ->
+	   #iq{type = set, lang = Lang, sub_el = #xmlel{name = <<"prefs">>} = SubEl} = IQ) ->
     try {case fxml:get_tag_attr_s(<<"default">>, SubEl) of
 	    <<"always">> -> always;
 	    <<"never">> -> never;
@@ -469,8 +469,9 @@ process_iq(#jid{luser = LUser, lserver = LServer},
 		    NewPrefs = prefs_el(Default, Always, Never, IQ#iq.xmlns),
 		    IQ#iq{type = result, sub_el = [NewPrefs]};
 		_Err ->
+		    Txt = <<"Database failure">>,
 		    IQ#iq{type = error,
-			sub_el = [SubEl, ?ERR_INTERNAL_SERVER_ERROR]}
+			sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]}
 	    end
     catch _:_ ->
 	    IQ#iq{type = error, sub_el = [SubEl, ?ERR_BAD_REQUEST]}
diff --git a/src/mod_mix.erl b/src/mod_mix.erl
index d8cf94ac3..c0835b74e 100644
--- a/src/mod_mix.erl
+++ b/src/mod_mix.erl
@@ -132,8 +132,9 @@ process_iq(From, To,
 	{error, Err} ->
 	    IQ#iq{type = error, sub_el = [SubEl, Err]}
     end;
-process_iq(_From, _To, #iq{sub_el = SubEl} = IQ) ->
-    IQ#iq{type = error, sub_el = [SubEl, ?ERR_BAD_REQUEST]}.
+process_iq(_From, _To, #iq{sub_el = SubEl, lang = Lang} = IQ) ->
+    Txt = <<"Unsupported MIX query">>,
+    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_BAD_REQUEST(Lang, Txt)]}.
 
 %%%===================================================================
 %%% gen_server callbacks
diff --git a/src/mod_muc.erl b/src/mod_muc.erl
index 0d37a236e..9d4b4985c 100644
--- a/src/mod_muc.erl
+++ b/src/mod_muc.erl
@@ -1056,7 +1056,9 @@ iq_set_register_info(ServerHost, Host, From, Nick,
 	  ErrText = <<"That nickname is registered by another "
 		      "person">>,
 	  {error, ?ERRT_CONFLICT(Lang, ErrText)};
-      _ -> {error, ?ERR_INTERNAL_SERVER_ERROR}
+      _ ->
+	  Txt = <<"Database failure">>,
+	  {error, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)}
     end.
 
 process_iq_register_set(ServerHost, Host, From, SubEl,
@@ -1073,7 +1075,9 @@ process_iq_register_set(ServerHost, Host, From, SubEl,
 		  {?NS_XDATA, <<"submit">>} ->
 		      XData = jlib:parse_xdata_submit(XEl),
 		      case XData of
-			invalid -> {error, ?ERR_BAD_REQUEST};
+			invalid ->
+			      Txt = <<"Incorrect data form">>,
+			      {error, ?ERRT_BAD_REQUEST(Lang, Txt)};
 			_ ->
 			    case lists:keysearch(<<"nick">>, 1, XData) of
 			      {value, {_, [Nick]}} when Nick /= <<"">> ->
diff --git a/src/mod_offline.erl b/src/mod_offline.erl
index fa6a961fe..54eda165c 100644
--- a/src/mod_offline.erl
+++ b/src/mod_offline.erl
@@ -387,8 +387,9 @@ handle_offline_query(#jid{luser = U, lserver = S} = From,
 	    end
     end,
     IQ#iq{type = result, sub_el = []};
-handle_offline_query(_From, _To, #iq{sub_el = SubEl} = IQ) ->
-    IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}.
+handle_offline_query(_From, _To, #iq{sub_el = SubEl, lang = Lang} = IQ) ->
+    Txt = <<"Query to another users is forbidden">>,
+    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}.
 
 handle_offline_items_view(JID, #xmlel{children = Items}) ->
     {U, S, R} = jid:tolower(JID),
diff --git a/src/mod_ping.erl b/src/mod_ping.erl
index e8a977ded..305c6a69c 100644
--- a/src/mod_ping.erl
+++ b/src/mod_ping.erl
@@ -204,13 +204,14 @@ code_change(_OldVsn, State, _Extra) -> {ok, State}.
 %% Hook callbacks
 %%====================================================================
 iq_ping(_From, _To,
-	#iq{type = Type, sub_el = SubEl} = IQ) ->
+	#iq{type = Type, sub_el = SubEl, lang = Lang} = IQ) ->
     case {Type, SubEl} of
       {get, #xmlel{name = <<"ping">>}} ->
 	  IQ#iq{type = result, sub_el = []};
       _ ->
+	  Txt = <<"Ping query is incorrect">>,
 	  IQ#iq{type = error,
-		sub_el = [SubEl, ?ERR_FEATURE_NOT_IMPLEMENTED]}
+		sub_el = [SubEl, ?ERRT_BAD_REQUEST(Lang, Txt)]}
     end.
 
 user_online(_SID, JID, _Info) ->
diff --git a/src/mod_private.erl b/src/mod_private.erl
index f3dceeaaf..b4b064502 100644
--- a/src/mod_private.erl
+++ b/src/mod_private.erl
@@ -73,52 +73,58 @@ stop(Host) ->
 				     ?NS_PRIVATE).
 
 process_sm_iq(#jid{luser = LUser, lserver = LServer},
-	      #jid{luser = LUser, lserver = LServer}, IQ)
+	      #jid{luser = LUser, lserver = LServer}, #iq{lang = Lang} = IQ)
     when IQ#iq.type == set ->
     case IQ#iq.sub_el of
       #xmlel{name = <<"query">>, children = Xmlels} ->
 	  case filter_xmlels(Xmlels) of
 	    [] ->
+		Txt = <<"No private data found in this query">>,
 		IQ#iq{type = error,
-		      sub_el = [IQ#iq.sub_el, ?ERR_NOT_ACCEPTABLE]};
+		      sub_el = [IQ#iq.sub_el, ?ERRT_NOT_ACCEPTABLE(Lang, Txt)]};
 	    Data ->
 		set_data(LUser, LServer, Data),
 		IQ#iq{type = result, sub_el = []}
 	  end;
       _ ->
+	  Txt = <<"No query found">>,
 	  IQ#iq{type = error,
-		sub_el = [IQ#iq.sub_el, ?ERR_NOT_ACCEPTABLE]}
+		sub_el = [IQ#iq.sub_el, ?ERRT_NOT_ACCEPTABLE(Lang, Txt)]}
     end;
 %%
 process_sm_iq(#jid{luser = LUser, lserver = LServer},
-	      #jid{luser = LUser, lserver = LServer}, IQ)
+	      #jid{luser = LUser, lserver = LServer}, #iq{lang = Lang} = IQ)
     when IQ#iq.type == get ->
     case IQ#iq.sub_el of
       #xmlel{name = <<"query">>, attrs = Attrs,
 	     children = Xmlels} ->
 	  case filter_xmlels(Xmlels) of
 	    [] ->
+		Txt = <<"No private data found in this query">>,
 		IQ#iq{type = error,
-		      sub_el = [IQ#iq.sub_el, ?ERR_BAD_FORMAT]};
+		      sub_el = [IQ#iq.sub_el, ?ERRT_BAD_FORMAT(Lang, Txt)]};
 	    Data ->
 		case catch get_data(LUser, LServer, Data) of
 		  {'EXIT', _Reason} ->
+		      Txt = <<"Database failure">>,
 		      IQ#iq{type = error,
 			    sub_el =
-				[IQ#iq.sub_el, ?ERR_INTERNAL_SERVER_ERROR]};
+				[IQ#iq.sub_el, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]};
 		  Storage_Xmlels ->
 		      IQ#iq{type = result,
 			    sub_el = [?Xmlel_Query(Attrs, Storage_Xmlels)]}
 		end
 	  end;
       _ ->
+	  Txt = <<"No query found">>,
 	  IQ#iq{type = error,
-		sub_el = [IQ#iq.sub_el, ?ERR_BAD_FORMAT]}
+		sub_el = [IQ#iq.sub_el, ?ERRT_BAD_FORMAT(Lang, Txt)]}
     end;
 %%
-process_sm_iq(_From, _To, IQ) ->
+process_sm_iq(_From, _To, #iq{lang = Lang} = IQ) ->
+    Txt = <<"Query to another users is forbidden">>,
     IQ#iq{type = error,
-	  sub_el = [IQ#iq.sub_el, ?ERR_FORBIDDEN]}.
+	  sub_el = [IQ#iq.sub_el, ?ERRT_FORBIDDEN(Lang, Txt)]}.
 
 filter_xmlels(Xmlels) -> filter_xmlels(Xmlels, []).
 
diff --git a/src/mod_proxy65_service.erl b/src/mod_proxy65_service.erl
index 8b4644ba8..d64afa04d 100644
--- a/src/mod_proxy65_service.erl
+++ b/src/mod_proxy65_service.erl
@@ -150,7 +150,7 @@ process_iq(_,
 		      children = iq_vcard(Lang)}]};
 %% bytestreams info request
 process_iq(JID,
-	   #iq{type = get, sub_el = SubEl,
+	   #iq{type = get, sub_el = SubEl, lang = Lang,
 	       xmlns = ?NS_BYTESTREAMS} =
 	       IQ,
 	   #state{acl = ACL, stream_addr = StreamAddr,
@@ -165,11 +165,12 @@ process_iq(JID,
 			    attrs = [{<<"xmlns">>, ?NS_BYTESTREAMS}],
 			    children = StreamHostEl}]};
       deny ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}
+	  Txt = <<"Denied by ACL">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}
     end;
 %% bytestream activation request
 process_iq(InitiatorJID,
-	   #iq{type = set, sub_el = SubEl,
+	   #iq{type = set, sub_el = SubEl, lang = Lang,
 	       xmlns = ?NS_BYTESTREAMS} =
 	       IQ,
 	   #state{acl = ACL, serverhost = ServerHost}) ->
@@ -194,22 +195,27 @@ process_iq(InitiatorJID,
 		    of
 		  ok -> IQ#iq{type = result, sub_el = []};
 		  false ->
+		      Txt = <<"Failed to activate bytestream">>,
 		      IQ#iq{type = error,
-			    sub_el = [SubEl, ?ERR_ITEM_NOT_FOUND]};
+			    sub_el = [SubEl, ?ERRT_ITEM_NOT_FOUND(Lang, Txt)]};
 		  limit ->
+		      Txt = <<"Too many active bytestreams">>,
 		      IQ#iq{type = error,
-			    sub_el = [SubEl, ?ERR_RESOURCE_CONSTRAINT]};
+			    sub_el = [SubEl, ?ERRT_RESOURCE_CONSTRAINT(Lang, Txt)]};
 		  conflict ->
-		      IQ#iq{type = error, sub_el = [SubEl, ?ERR_CONFLICT]};
+		      Txt = <<"Bytestream already activated">>,
+		      IQ#iq{type = error, sub_el = [SubEl, ?ERRT_CONFLICT(Lang, Txt)]};
 		  _ ->
 		      IQ#iq{type = error,
 			    sub_el = [SubEl, ?ERR_INTERNAL_SERVER_ERROR]}
 		end;
 	    _ ->
-		IQ#iq{type = error, sub_el = [SubEl, ?ERR_BAD_REQUEST]}
+		Txt = <<"Malformed JID">>,
+		IQ#iq{type = error, sub_el = [SubEl, ?ERRT_BAD_REQUEST(Lang, Txt)]}
 	  end;
       deny ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]}
+	  Txt = <<"Denied by ACL">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]}
     end;
 %% Unknown "set" or "get" request
 process_iq(_, #iq{type = Type, sub_el = SubEl} = IQ, _)
diff --git a/src/mod_roster.erl b/src/mod_roster.erl
index 997544b1e..35072e5f8 100644
--- a/src/mod_roster.erl
+++ b/src/mod_roster.erl
@@ -137,13 +137,14 @@ process_iq(From, To, IQ) when ((From#jid.luser == <<"">>) andalso (From#jid.reso
     process_iq_manager(From, To, IQ);
 
 process_iq(From, To, IQ) ->
-    #iq{sub_el = SubEl} = IQ,
+    #iq{sub_el = SubEl, lang = Lang} = IQ,
     #jid{lserver = LServer} = From,
     case lists:member(LServer, ?MYHOSTS) of
       true -> process_local_iq(From, To, IQ);
       _ ->
+	  Txt = <<"The query is only allowed from local users">>,
 	  IQ#iq{type = error,
-		sub_el = [SubEl, ?ERR_ITEM_NOT_FOUND]}
+		sub_el = [SubEl, ?ERRT_ITEM_NOT_FOUND(Lang, Txt)]}
     end.
 
 process_local_iq(From, To, #iq{type = Type} = IQ) ->
@@ -479,12 +480,13 @@ get_roster_by_jid_t(LUser, LServer, LJID, riak) ->
             exit(Err)
     end.
 
-try_process_iq_set(From, To, #iq{sub_el = SubEl} = IQ) ->
+try_process_iq_set(From, To, #iq{sub_el = SubEl, lang = Lang} = IQ) ->
     #jid{server = Server} = From,
     Access = gen_mod:get_module_opt(Server, ?MODULE, access, fun(A) when is_atom(A) -> A end, all),
     case acl:match_rule(Server, Access, From) of
 	deny ->
-	    IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	    Txt = <<"Denied by ACL">>,
+	    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
 	allow ->
 	    process_iq_set(From, To, IQ)
     end.
@@ -1616,8 +1618,9 @@ process_iq_manager(From, To, IQ) ->
 	true ->
 	    process_iq_manager2(MatchDomain, To, IQ);
 	false ->
-	    #iq{sub_el = SubEl} = IQ,
-	    IQ#iq{type = error, sub_el = [SubEl, ?ERR_BAD_REQUEST]}
+	    #iq{sub_el = SubEl, lang = Lang} = IQ,
+	    Txt = <<"Roster management is not allowed from this domain">>,
+	    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_BAD_REQUEST(Lang, Txt)]}
     end.
 
 process_iq_manager2(MatchDomain, To, IQ) ->
diff --git a/src/mod_sic.erl b/src/mod_sic.erl
index 3ffd9c917..b4eae0daf 100644
--- a/src/mod_sic.erl
+++ b/src/mod_sic.erl
@@ -60,8 +60,9 @@ process_local_iq(#jid{user = User, server = Server,
 		 _To, #iq{type = get, sub_el = _SubEl} = IQ) ->
     get_ip({User, Server, Resource}, IQ);
 process_local_iq(_From, _To,
-		 #iq{type = set, sub_el = SubEl} = IQ) ->
-    IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]}.
+		 #iq{type = set, sub_el = SubEl, lang = Lang} = IQ) ->
+    Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]}.
 
 process_sm_iq(#jid{user = User, server = Server,
 		   resource = Resource},
@@ -69,14 +70,17 @@ process_sm_iq(#jid{user = User, server = Server,
 	      #iq{type = get, sub_el = _SubEl} = IQ) ->
     get_ip({User, Server, Resource}, IQ);
 process_sm_iq(_From, _To,
-	      #iq{type = get, sub_el = SubEl} = IQ) ->
-    IQ#iq{type = error, sub_el = [SubEl, ?ERR_FORBIDDEN]};
+	      #iq{type = get, sub_el = SubEl, lang = Lang} = IQ) ->
+    Txt = <<"Query to another users is forbidden">>,
+    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_FORBIDDEN(Lang, Txt)]};
 process_sm_iq(_From, _To,
-	      #iq{type = set, sub_el = SubEl} = IQ) ->
-    IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]}.
+	      #iq{type = set, sub_el = SubEl, lang = Lang} = IQ) ->
+    Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+    IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]}.
 
 get_ip({User, Server, Resource},
-       #iq{sub_el =
+       #iq{lang = Lang,
+	   sub_el =
 	       #xmlel{name = Name, attrs = Attrs} = SubEl} =
 	   IQ) ->
     case ejabberd_sm:get_user_ip(User, Server, Resource) of
@@ -88,8 +92,9 @@ get_ip({User, Server, Resource},
 				[{xmlcdata,
 				  iolist_to_binary(jlib:ip_to_list(IP))}]}]};
       _ ->
+	  Txt = <<"User session not found">>,
 	  IQ#iq{type = error,
-		sub_el = [SubEl, ?ERR_INTERNAL_SERVER_ERROR]}
+		sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]}
     end.
 
 mod_opt_type(iqdisc) -> fun gen_iq_handler:check_type/1;
diff --git a/src/mod_stats.erl b/src/mod_stats.erl
index 0328aec30..c14cf8d15 100644
--- a/src/mod_stats.erl
+++ b/src/mod_stats.erl
@@ -50,17 +50,18 @@ stop(Host) ->
 
 process_local_iq(_From, To,
 		 #iq{id = _ID, type = Type, xmlns = XMLNS,
-		     sub_el = SubEl} =
+		     sub_el = SubEl, lang = Lang} =
 		     IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  #xmlel{children = Els} = SubEl,
 	  Node = str:tokens(fxml:get_tag_attr_s(<<"node">>, SubEl),
 			    <<"/">>),
 	  Names = get_names(Els, []),
-	  case get_local_stats(To#jid.server, Node, Names) of
+	  case get_local_stats(To#jid.server, Node, Names, Lang) of
 	    {result, Res} ->
 		IQ#iq{type = result,
 		      sub_el =
@@ -87,18 +88,18 @@ get_names([_ | Els], Res) -> get_names(Els, Res).
 	#xmlel{name = <<"stat">>, attrs = [{<<"name">>, Name}],
 	       children = []}).
 
-get_local_stats(_Server, [], []) ->
+get_local_stats(_Server, [], [], _Lang) ->
     {result,
      [?STAT(<<"users/online">>), ?STAT(<<"users/total">>),
       ?STAT(<<"users/all-hosts/online">>),
       ?STAT(<<"users/all-hosts/total">>)]};
-get_local_stats(Server, [], Names) ->
+get_local_stats(Server, [], Names, _Lang) ->
     {result,
      lists:map(fun (Name) -> get_local_stat(Server, [], Name)
 	       end,
 	       Names)};
 get_local_stats(_Server, [<<"running nodes">>, _],
-		[]) ->
+		[], _Lang) ->
     {result,
      [?STAT(<<"time/uptime">>), ?STAT(<<"time/cputime">>),
       ?STAT(<<"users/online">>),
@@ -107,16 +108,19 @@ get_local_stats(_Server, [<<"running nodes">>, _],
       ?STAT(<<"transactions/restarted">>),
       ?STAT(<<"transactions/logged">>)]};
 get_local_stats(_Server, [<<"running nodes">>, ENode],
-		Names) ->
+		Names, Lang) ->
     case search_running_node(ENode) of
-      false -> {error, ?ERR_ITEM_NOT_FOUND};
+      false ->
+	    Txt = <<"No running node found">>,
+	    {error, ?ERRT_ITEM_NOT_FOUND(Lang, Txt)};
       Node ->
 	  {result,
 	   lists:map(fun (Name) -> get_node_stat(Node, Name) end,
 		     Names)}
     end;
-get_local_stats(_Server, _, _) ->
-    {error, ?ERR_FEATURE_NOT_IMPLEMENTED}.
+get_local_stats(_Server, _, _, Lang) ->
+    Txt = <<"No statistics found for this item">>,
+    {error, ?ERRT_FEATURE_NOT_IMPLEMENTED(Lang, Txt)}.
 
 -define(STATVAL(Val, Unit),
 	#xmlel{name = <<"stat">>,
diff --git a/src/mod_time.erl b/src/mod_time.erl
index 8bfe9f9f9..740b654a7 100644
--- a/src/mod_time.erl
+++ b/src/mod_time.erl
@@ -51,10 +51,11 @@ stop(Host) ->
 				     ?NS_TIME).
 
 process_local_iq(_From, _To,
-		 #iq{type = Type, sub_el = SubEl} = IQ) ->
+		 #iq{type = Type, sub_el = SubEl, lang = Lang} = IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  Now_universal = calendar:universal_time(),
 	  Now_local = calendar:universal_time_to_local_time(Now_universal),
diff --git a/src/mod_vcard.erl b/src/mod_vcard.erl
index 256dc5de7..4d7c80d57 100644
--- a/src/mod_vcard.erl
+++ b/src/mod_vcard.erl
@@ -152,7 +152,8 @@ process_local_iq(_From, _To,
 		 #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  IQ#iq{type = result,
 		sub_el =
@@ -176,7 +177,7 @@ process_local_iq(_From, _To,
     end.
 
 process_sm_iq(From, To,
-	      #iq{type = Type, sub_el = SubEl} = IQ) ->
+	      #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case Type of
       set ->
 	  #jid{user = User, lserver = LServer} = From,
@@ -185,14 +186,16 @@ process_sm_iq(From, To,
 		set_vcard(User, LServer, SubEl),
 		IQ#iq{type = result, sub_el = []};
 	    false ->
-		IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]}
+		Txt = <<"The query is only allowed from local users">>,
+		IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]}
 	  end;
       get ->
 	  #jid{luser = LUser, lserver = LServer} = To,
 	  case get_vcard(LUser, LServer) of
 	    error ->
+		Txt = <<"Database failure">>,
 		IQ#iq{type = error,
-		      sub_el = [SubEl, ?ERR_INTERNAL_SERVER_ERROR]};
+		      sub_el = [SubEl, ?ERRT_INTERNAL_SERVER_ERROR(Lang, Txt)]};
 	    [] ->
 		IQ#iq{type = result,
 		      sub_el = [#xmlel{name = <<"vCard">>,
@@ -422,15 +425,17 @@ do_route(ServerHost, From, To, Packet) ->
 		       XDataEl = find_xdata_el(SubEl),
 		       case XDataEl of
 			 false ->
-			     Err = jlib:make_error_reply(Packet,
-							 ?ERR_BAD_REQUEST),
+			     Txt = <<"Data form not found">>,
+			     Err = jlib:make_error_reply(
+				     Packet, ?ERRT_BAD_REQUEST(Lang, Txt)),
 			     ejabberd_router:route(To, From, Err);
 			 _ ->
 			     XData = jlib:parse_xdata_submit(XDataEl),
 			     case XData of
 			       invalid ->
-				   Err = jlib:make_error_reply(Packet,
-							       ?ERR_BAD_REQUEST),
+				   Txt = <<"Incorrect data form">>,
+				   Err = jlib:make_error_reply(
+					   Packet, ?ERRT_BAD_REQUEST(Lang, Txt)),
 				   ejabberd_router:route(To, From, Err);
 			       _ ->
 				   ResIQ = IQ#iq{type = result,
@@ -470,7 +475,8 @@ do_route(ServerHost, From, To, Packet) ->
 	     #iq{type = Type, xmlns = ?NS_DISCO_INFO, lang = Lang} ->
 		 case Type of
 		   set ->
-		       Err = jlib:make_error_reply(Packet, ?ERR_NOT_ALLOWED),
+		       Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+		       Err = jlib:make_error_reply(Packet, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 		       ejabberd_router:route(To, From, Err);
 		   get ->
 		       Info = ejabberd_hooks:run_fold(disco_info, ServerHost,
@@ -516,10 +522,11 @@ do_route(ServerHost, From, To, Packet) ->
 						       ++ Info}]},
 		       ejabberd_router:route(To, From, jlib:iq_to_xml(ResIQ))
 		 end;
-	     #iq{type = Type, xmlns = ?NS_DISCO_ITEMS} ->
+	     #iq{type = Type, lang = Lang, xmlns = ?NS_DISCO_ITEMS} ->
 		 case Type of
 		   set ->
-		       Err = jlib:make_error_reply(Packet, ?ERR_NOT_ALLOWED),
+		       Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+		       Err = jlib:make_error_reply(Packet, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 		       ejabberd_router:route(To, From, Err);
 		   get ->
 		       ResIQ = IQ#iq{type = result,
diff --git a/src/mod_vcard_ldap.erl b/src/mod_vcard_ldap.erl
index 98aaf9362..46f81af09 100644
--- a/src/mod_vcard_ldap.erl
+++ b/src/mod_vcard_ldap.erl
@@ -206,7 +206,8 @@ process_local_iq(_From, _To,
 		 #iq{type = Type, lang = Lang, sub_el = SubEl} = IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  IQ#iq{type = result,
 		sub_el =
@@ -240,10 +241,11 @@ process_sm_iq(_From, #jid{lserver = LServer} = To,
 
 process_vcard_ldap(To, IQ, Server) ->
     {ok, State} = eldap_utils:get_state(Server, ?PROCNAME),
-    #iq{type = Type, sub_el = SubEl} = IQ,
+    #iq{type = Type, sub_el = SubEl, lang = Lang} = IQ,
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  #jid{luser = LUser} = To,
 	  LServer = State#state.serverhost,
@@ -455,15 +457,17 @@ route(State, From, To, Packet) ->
 		       XDataEl = find_xdata_el(SubEl),
 		       case XDataEl of
 			 false ->
-			     Err = jlib:make_error_reply(Packet,
-							 ?ERR_BAD_REQUEST),
+			     Txt = <<"Data form not found">>,
+			     Err = jlib:make_error_reply(
+				     Packet, ?ERRT_BAD_REQUEST(Lang, Txt)),
 			     ejabberd_router:route(To, From, Err);
 			 _ ->
 			     XData = jlib:parse_xdata_submit(XDataEl),
 			     case XData of
 			       invalid ->
-				   Err = jlib:make_error_reply(Packet,
-							       ?ERR_BAD_REQUEST),
+				   Txt = <<"Incorrect data form">>,
+				   Err = jlib:make_error_reply(
+					   Packet, ?ERRT_BAD_REQUEST(Lang, Txt)),
 				   ejabberd_router:route(To, From, Err);
 			       _ ->
 				   ResIQ = IQ#iq{type = result,
@@ -505,7 +509,8 @@ route(State, From, To, Packet) ->
 	     #iq{type = Type, xmlns = ?NS_DISCO_INFO, lang = Lang} ->
 		 case Type of
 		   set ->
-		       Err = jlib:make_error_reply(Packet, ?ERR_NOT_ALLOWED),
+		       Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+		       Err = jlib:make_error_reply(Packet, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 		       ejabberd_router:route(To, From, Err);
 		   get ->
 		       Info = ejabberd_hooks:run_fold(disco_info, ServerHost,
@@ -545,10 +550,11 @@ route(State, From, To, Packet) ->
 						       ++ Info}]},
 		       ejabberd_router:route(To, From, jlib:iq_to_xml(ResIQ))
 		 end;
-	     #iq{type = Type, xmlns = ?NS_DISCO_ITEMS} ->
+	     #iq{type = Type, lang = Lang, xmlns = ?NS_DISCO_ITEMS} ->
 		 case Type of
 		   set ->
-		       Err = jlib:make_error_reply(Packet, ?ERR_NOT_ALLOWED),
+		       Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+		       Err = jlib:make_error_reply(Packet, ?ERRT_NOT_ALLOWED(Lang, Txt)),
 		       ejabberd_router:route(To, From, Err);
 		   get ->
 		       ResIQ = IQ#iq{type = result,
diff --git a/src/mod_version.erl b/src/mod_version.erl
index 0e3b96bd1..7f7759f2d 100644
--- a/src/mod_version.erl
+++ b/src/mod_version.erl
@@ -52,11 +52,12 @@ stop(Host) ->
 
 process_local_iq(_From, To,
 		 #iq{id = _ID, type = Type, xmlns = _XMLNS,
-		     sub_el = SubEl} =
+		     sub_el = SubEl, lang = Lang} =
 		     IQ) ->
     case Type of
       set ->
-	  IQ#iq{type = error, sub_el = [SubEl, ?ERR_NOT_ALLOWED]};
+	  Txt = <<"Value 'set' of 'type' attribute is not allowed">>,
+	  IQ#iq{type = error, sub_el = [SubEl, ?ERRT_NOT_ALLOWED(Lang, Txt)]};
       get ->
 	  Host = To#jid.lserver,
 	  OS = case gen_mod:get_module_opt(Host, ?MODULE, show_os,
diff --git a/src/node_dag.erl b/src/node_dag.erl
index cbb8e18c6..09ee85f91 100644
--- a/src/node_dag.erl
+++ b/src/node_dag.erl
@@ -77,8 +77,9 @@ publish_item(Nidx, Publisher, Model, MaxItems, ItemId, Payload) ->
 	#pubsub_node{options = Options} ->
 	    case find_opt(node_type, Options) of
 		collection ->
+		    Txt = <<"Publishing items to collection node is not allowed">>,
 		    {error,
-			?ERR_EXTENDED((?ERR_NOT_ALLOWED), <<"publish">>)};
+		     ?ERR_EXTENDED(?ERRT_NOT_ALLOWED(?MYLANG, Txt), <<"publish">>)};
 		_ ->
 		    node_hometree:publish_item(Nidx, Publisher, Model,
 			MaxItems, ItemId, Payload)
diff --git a/src/nodetree_dag.erl b/src/nodetree_dag.erl
index 8ac56b27d..a105db832 100644
--- a/src/nodetree_dag.erl
+++ b/src/nodetree_dag.erl
@@ -69,13 +69,13 @@ create_node(Key, Node, Type, Owner, Options, Parents) ->
 		Other -> Other
 	    end;
 	_ ->
-	    {error, ?ERR_CONFLICT}
+	    {error, ?ERRT_CONFLICT(?MYLANG, <<"Node already exists">>)}
     end.
 
 delete_node(Key, Node) ->
     case find_node(Key, Node) of
 	false ->
-	    {error, ?ERR_ITEM_NOT_FOUND};
+	    {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)};
 	Record ->
 	    lists:foreach(fun (#pubsub_node{options = Opts} = Child) ->
 			NewOpts = remove_config_parent(Node, Opts),
@@ -99,7 +99,7 @@ get_node(Host, Node, _From) ->
 
 get_node(Host, Node) ->
     case find_node(Host, Node) of
-	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	false -> {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)};
 	Record -> Record
     end.
 
@@ -115,7 +115,7 @@ get_nodes(Key) ->
 get_parentnodes(Host, Node, _From) ->
     case find_node(Host, Node) of
 	false ->
-	    {error, ?ERR_ITEM_NOT_FOUND};
+	    {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)};
 	#pubsub_node{parents = Parents} ->
 	    Q = qlc:q([N
 			|| #pubsub_node{nodeid = {NHost, NNode}} = N
@@ -139,7 +139,7 @@ get_subnodes(Host, <<>>) ->
     get_subnodes_helper(Host, <<>>);
 get_subnodes(Host, Node) ->
     case find_node(Host, Node) of
-	false -> {error, ?ERR_ITEM_NOT_FOUND};
+	false -> {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)};
 	_ -> get_subnodes_helper(Host, Node)
     end.
 
@@ -238,7 +238,7 @@ validate_parentage(Key, Owners, [<<>> | T]) ->
 validate_parentage(Key, Owners, [ParentID | T]) ->
     case find_node(Key, ParentID) of
 	false ->
-	    {error, ?ERR_ITEM_NOT_FOUND};
+	    {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)};
 	#pubsub_node{owners = POwners, options = POptions} ->
 	    NodeType = find_opt(node_type, ?DEFAULT_NODETYPE, POptions),
 	    MutualOwners = [O || O <- Owners, PO <- POwners, O == PO],
diff --git a/src/nodetree_tree.erl b/src/nodetree_tree.erl
index e3f7e251e..ff8e3f64c 100644
--- a/src/nodetree_tree.erl
+++ b/src/nodetree_tree.erl
@@ -74,15 +74,15 @@ get_node(Host, Node, _From) ->
     get_node(Host, Node).
 
 get_node(Host, Node) ->
-    case catch mnesia:read({pubsub_node, {Host, Node}}) of
+    case mnesia:read({pubsub_node, {Host, Node}}) of
 	[Record] when is_record(Record, pubsub_node) -> Record;
-	_ -> {error, ?ERR_ITEM_NOT_FOUND}
+	_ -> {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)}
     end.
 
 get_node(Nidx) ->
-    case catch mnesia:index_read(pubsub_node, Nidx, #pubsub_node.id) of
+    case mnesia:index_read(pubsub_node, Nidx, #pubsub_node.id) of
 	[Record] when is_record(Record, pubsub_node) -> Record;
-	_ -> {error, ?ERR_ITEM_NOT_FOUND}
+	_ -> {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)}
     end.
 
 get_nodes(Host, _From) ->
@@ -147,7 +147,7 @@ get_subnodes_tree(Host, Node) ->
 
 create_node(Host, Node, Type, Owner, Options, Parents) ->
     BJID = jid:tolower(jid:remove_resource(Owner)),
-    case catch mnesia:read({pubsub_node, {Host, Node}}) of
+    case mnesia:read({pubsub_node, {Host, Node}}) of
 	[] ->
 	    ParentExists = case Host of
 		{_U, _S, _R} ->
@@ -183,7 +183,7 @@ create_node(Host, Node, Type, Owner, Options, Parents) ->
 		    {error, ?ERR_FORBIDDEN}
 	    end;
 	_ ->
-	    {error, ?ERR_CONFLICT}
+	    {error, ?ERRT_CONFLICT(?MYLANG, <<"Node already exists">>)}
     end.
 
 delete_node(Host, Node) ->
diff --git a/src/nodetree_tree_odbc.erl b/src/nodetree_tree_odbc.erl
index ef1c20b6b..6c139ad6c 100644
--- a/src/nodetree_tree_odbc.erl
+++ b/src/nodetree_tree_odbc.erl
@@ -93,7 +93,8 @@ set_node(Record) when is_record(Record, pubsub_node) ->
     end,
     case Nidx of
 	none ->
-	    {error, ?ERR_INTERNAL_SERVER_ERROR};
+	    Txt = <<"Node index not found">>,
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(?MYLANG, Txt)};
 	_ ->
 	    lists:foreach(fun ({Key, Value}) ->
 			SKey = iolist_to_binary(atom_to_list(Key)),
@@ -125,9 +126,9 @@ get_node(Host, Node) ->
 		    [<<"node">>, <<"parent">>, <<"type">>, <<"nodeid">>], [RItem]} ->
 	    raw_to_node(Host, RItem);
 	{'EXIT', _Reason} ->
-	    {error, ?ERR_INTERNAL_SERVER_ERROR};
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(?MYLANG, <<"Database failure">>)};
 	_ ->
-	    {error, ?ERR_ITEM_NOT_FOUND}
+	    {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)}
     end.
 
 get_node(Nidx) ->
@@ -140,9 +141,9 @@ get_node(Nidx) ->
 		    [<<"host">>, <<"node">>, <<"parent">>, <<"type">>], [[Host, Node, Parent, Type]]} ->
 	    raw_to_node(Host, [Node, Parent, Type, Nidx]);
 	{'EXIT', _Reason} ->
-	    {error, ?ERR_INTERNAL_SERVER_ERROR};
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(?MYLANG, <<"Database failure">>)};
 	_ ->
-	    {error, ?ERR_ITEM_NOT_FOUND}
+	    {error, ?ERRT_ITEM_NOT_FOUND(?MYLANG, <<"Node not found">>)}
     end.
 
 get_nodes(Host, _From) ->
@@ -211,7 +212,7 @@ get_subnodes_tree(Host, Node) ->
 create_node(Host, Node, Type, Owner, Options, Parents) ->
     BJID = jid:tolower(jid:remove_resource(Owner)),
     case nodeidx(Host, Node) of
-	{error, ?ERR_ITEM_NOT_FOUND} ->
+	{error, not_found} ->
 	    ParentExists = case Host of
 		{_U, _S, _R} ->
 		    %% This is special case for PEP handling
@@ -248,9 +249,9 @@ create_node(Host, Node, Type, Owner, Options, Parents) ->
 		    {error, ?ERR_FORBIDDEN}
 	    end;
 	{result, _} ->
-	    {error, ?ERR_CONFLICT};
-	Error ->
-	    Error
+	    {error, ?ERRT_CONFLICT(?MYLANG, <<"Node already exists">>)};
+	{error, db_fail} ->
+	    {error, ?ERRT_INTERNAL_SERVER_ERROR(?MYLANG, <<"Database failure">>)}
     end.
 
 delete_node(Host, Node) ->
@@ -303,9 +304,9 @@ nodeidx(Host, Node) ->
 	{selected, [<<"nodeid">>], [[Nidx]]} ->
 	    {result, Nidx};
 	{'EXIT', _Reason} ->
-	    {error, ?ERR_INTERNAL_SERVER_ERROR};
+	    {error, db_fail};
 	_ ->
-	    {error, ?ERR_ITEM_NOT_FOUND}
+	    {error, not_found}
     end.
 
 nodeowners(Nidx) ->
diff --git a/src/pubsub_subscription.erl b/src/pubsub_subscription.erl
index 22c904144..f990f6e38 100644
--- a/src/pubsub_subscription.erl
+++ b/src/pubsub_subscription.erl
@@ -237,31 +237,40 @@ var_xfield(?PUBSUB_SUBSCRIPTION_TYPE) -> subscription_type;
 var_xfield(?PUBSUB_SUBSCRIPTION_DEPTH) -> subscription_depth;
 var_xfield(_) -> {error, badarg}.
 
-val_xfield(deliver, [Val]) -> xopt_to_bool(Val);
-val_xfield(digest, [Val]) -> xopt_to_bool(Val);
-val_xfield(digest_frequency, [Val]) ->
+val_xfield(deliver = Opt, [Val]) -> xopt_to_bool(Opt, Val);
+val_xfield(digest = Opt, [Val]) -> xopt_to_bool(Opt, Val);
+val_xfield(digest_frequency = Opt, [Val]) ->
     case catch jlib:binary_to_integer(Val) of
 	N when is_integer(N) -> N;
-	_ -> {error, ?ERR_NOT_ACCEPTABLE}
+	_ ->
+	    Txt = <<"Value of '~s' should be integer">>,
+	    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Opt])),
+	    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}
     end;
 val_xfield(expire, [Val]) -> jlib:datetime_string_to_timestamp(Val);
-val_xfield(include_body, [Val]) -> xopt_to_bool(Val);
+val_xfield(include_body = Opt, [Val]) -> xopt_to_bool(Opt, Val);
 val_xfield(show_values, Vals) -> Vals;
 val_xfield(subscription_type, [<<"items">>]) -> items;
 val_xfield(subscription_type, [<<"nodes">>]) -> nodes;
 val_xfield(subscription_depth, [<<"all">>]) -> all;
-val_xfield(subscription_depth, [Depth]) ->
+val_xfield(subscription_depth = Opt, [Depth]) ->
     case catch jlib:binary_to_integer(Depth) of
 	N when is_integer(N) -> N;
-	_ -> {error, ?ERR_NOT_ACCEPTABLE}
+	_ ->
+	    Txt = <<"Value of '~s' should be integer">>,
+	    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Opt])),
+	    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}
     end.
 
 %% Convert XForm booleans to Erlang booleans.
-xopt_to_bool(<<"0">>) -> false;
-xopt_to_bool(<<"1">>) -> true;
-xopt_to_bool(<<"false">>) -> false;
-xopt_to_bool(<<"true">>) -> true;
-xopt_to_bool(_) -> {error, ?ERR_NOT_ACCEPTABLE}.
+xopt_to_bool(_, <<"0">>) -> false;
+xopt_to_bool(_, <<"1">>) -> true;
+xopt_to_bool(_, <<"false">>) -> false;
+xopt_to_bool(_, <<"true">>) -> true;
+xopt_to_bool(Option, _) ->
+    Txt = <<"Value of '~s' should be boolean">>,
+    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Option])),
+    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}.
 
 -spec(get_option_xfield/3 ::
     (
diff --git a/src/pubsub_subscription_odbc.erl b/src/pubsub_subscription_odbc.erl
index 149308ad0..afd31c818 100644
--- a/src/pubsub_subscription_odbc.erl
+++ b/src/pubsub_subscription_odbc.erl
@@ -200,31 +200,40 @@ var_xfield(?PUBSUB_SUBSCRIPTION_TYPE) -> subscription_type;
 var_xfield(?PUBSUB_SUBSCRIPTION_DEPTH) -> subscription_depth;
 var_xfield(_) -> {error, badarg}.
 
-val_xfield(deliver, [Val]) -> xopt_to_bool(Val);
-val_xfield(digest, [Val]) -> xopt_to_bool(Val);
-val_xfield(digest_frequency, [Val]) ->
+val_xfield(deliver = Opt, [Val]) -> xopt_to_bool(Opt, Val);
+val_xfield(digest = Opt, [Val]) -> xopt_to_bool(Opt, Val);
+val_xfield(digest_frequency = Opt, [Val]) ->
     case catch jlib:binary_to_integer(Val) of
 	N when is_integer(N) -> N;
-	_ -> {error, ?ERR_NOT_ACCEPTABLE}
+	_ ->
+	    Txt = <<"Value of '~s' should be integer">>,
+	    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Opt])),
+	    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}
     end;
 val_xfield(expire, [Val]) -> jlib:datetime_string_to_timestamp(Val);
-val_xfield(include_body, [Val]) -> xopt_to_bool(Val);
+val_xfield(include_body = Opt, [Val]) -> xopt_to_bool(Opt, Val);
 val_xfield(show_values, Vals) -> Vals;
 val_xfield(subscription_type, [<<"items">>]) -> items;
 val_xfield(subscription_type, [<<"nodes">>]) -> nodes;
 val_xfield(subscription_depth, [<<"all">>]) -> all;
-val_xfield(subscription_depth, [Depth]) ->
+val_xfield(subscription_depth = Opt, [Depth]) ->
     case catch jlib:binary_to_integer(Depth) of
 	N when is_integer(N) -> N;
-	_ -> {error, ?ERR_NOT_ACCEPTABLE}
+	_ ->
+	    Txt = <<"Value of '~s' should be integer">>,
+	    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Opt])),
+	    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}
     end.
 
 %% Convert XForm booleans to Erlang booleans.
-xopt_to_bool(<<"0">>) -> false;
-xopt_to_bool(<<"1">>) -> true;
-xopt_to_bool(<<"false">>) -> false;
-xopt_to_bool(<<"true">>) -> true;
-xopt_to_bool(_) -> {error, ?ERR_NOT_ACCEPTABLE}.
+xopt_to_bool(_, <<"0">>) -> false;
+xopt_to_bool(_, <<"1">>) -> true;
+xopt_to_bool(_, <<"false">>) -> false;
+xopt_to_bool(_, <<"true">>) -> true;
+xopt_to_bool(Option, _) ->
+    Txt = <<"Value of '~s' should be boolean">>,
+    ErrTxt = iolist_to_binary(io_lib:format(Txt, [Option])),
+    {error, ?ERRT_NOT_ACCEPTABLE(?MYLANG, ErrTxt)}.
 
 %% Return a field for an XForm for Key, with data filled in, if
 %% applicable, from Options.