--- ./Makefile.in.orig	2014-02-19 12:30:54.040272078 +0100
+++ ./Makefile.in	2014-02-19 12:31:21.743269418 +0100
@@ -43,11 +43,11 @@
 	./regression
 
 install:	$(TARGETLIB)
-	$(MKDIR) $(libdir)
-	$(MKDIR) $(includedir)
-	$(INSTALL_DATA) $(TARGETLIB) $(libdir)/$(TARGETLIB)
+	$(MKDIR) $(DESTDIR)$(libdir)
+	$(MKDIR) $(DESTDIR)$(includedir)
+	$(INSTALL_DATA) $(TARGETLIB) $(DESTDIR)$(libdir)/$(TARGETLIB)
 	for i in $(TARGETINCS);do \
-	(set -x;$(INSTALL_DATA) $(srcdir)/$$i $(includedir)); \
+	(set -x;$(INSTALL_DATA) $(srcdir)/$$i $(DESTDIR)$(includedir)); \
 	done
 
 regression: regression.o $(TARGETLIB)