diff -up mozilla/content/base/src/nsStyleLinkElement.cpp.475136 mozilla/content/base/src/nsStyleLinkElement.cpp
--- content/base/src/nsStyleLinkElement.cpp.475136	2005-04-19 03:27:09.000000000 +0200
+++ content/base/src/nsStyleLinkElement.cpp	2009-02-17 18:01:21.000000000 +0100
@@ -63,10 +63,7 @@ nsStyleLinkElement::nsStyleLinkElement()
 
 nsStyleLinkElement::~nsStyleLinkElement()
 {
-  nsCOMPtr<nsICSSStyleSheet> cssSheet = do_QueryInterface(mStyleSheet);
-  if (cssSheet) {
-    cssSheet->SetOwningNode(nsnull);
-  }
+  nsStyleLinkElement::SetStyleSheet(nsnull);
 }
 
 NS_IMETHODIMP 
@@ -199,7 +196,7 @@ nsStyleLinkElement::UpdateStyleSheet(nsI
     aOldDocument->BeginUpdate(UPDATE_STYLE);
     aOldDocument->RemoveStyleSheet(mStyleSheet);
     aOldDocument->EndUpdate(UPDATE_STYLE);
-    mStyleSheet = nsnull;
+    nsStyleLinkElement::SetStyleSheet(nsnull);
   }
 
   if (mDontLoadStyle || !mUpdatesEnabled) {
@@ -245,7 +242,7 @@ nsStyleLinkElement::UpdateStyleSheet(nsI
     doc->BeginUpdate(UPDATE_STYLE);
     doc->RemoveStyleSheet(mStyleSheet);
     doc->EndUpdate(UPDATE_STYLE);
-    mStyleSheet = nsnull;
+    nsStyleLinkElement::SetStyleSheet(nsnull);
   }
 
   if (!uri && !isInline) {
diff -up mozilla/content/base/src/nsStyleLinkElement.h.475136 mozilla/content/base/src/nsStyleLinkElement.h
--- content/base/src/nsStyleLinkElement.h.475136	2004-09-09 19:32:34.000000000 +0200
+++ content/base/src/nsStyleLinkElement.h	2009-02-17 18:12:08.000000000 +0100
@@ -72,6 +72,7 @@ public:
 
   static void ParseLinkTypes(const nsAString& aTypes, nsStringArray& aResult);
 
+
 protected:
   virtual void GetStyleSheetURL(PRBool* aIsInline,
                                 nsIURI** aURI) = 0;
@@ -79,13 +80,16 @@ protected:
                                  nsAString& aType,
                                  nsAString& aMedia,
                                  PRBool* aIsAlternate) = 0;
+  nsIStyleSheet* GetStyleSheet() { return mStyleSheet; }
 
 
-  nsCOMPtr<nsIStyleSheet> mStyleSheet;
   nsCOMPtr<nsIParser> mParser;
   PRPackedBool mDontLoadStyle;
   PRPackedBool mUpdatesEnabled;
   PRUint32 mLineNumber;
+
+private:
+  nsCOMPtr<nsIStyleSheet> mStyleSheet;
 };
 
 #endif /* nsStyleLinkElement_h___ */
diff -up mozilla/content/html/content/src/nsHTMLLinkElement.cpp.475136 mozilla/content/html/content/src/nsHTMLLinkElement.cpp
--- content/html/content/src/nsHTMLLinkElement.cpp.475136	2005-08-10 22:21:42.000000000 +0200
+++ content/html/content/src/nsHTMLLinkElement.cpp	2009-02-17 18:14:51.000000000 +0100
@@ -159,7 +159,7 @@ NS_IMPL_DOM_CLONENODE(nsHTMLLinkElement)
 NS_IMETHODIMP
 nsHTMLLinkElement::GetDisabled(PRBool* aDisabled)
 {
-  nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(mStyleSheet));
+  nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(GetStyleSheet()));
   nsresult result = NS_OK;
 
   if (ss) {
@@ -174,7 +174,7 @@ nsHTMLLinkElement::GetDisabled(PRBool* a
 NS_IMETHODIMP 
 nsHTMLLinkElement::SetDisabled(PRBool aDisabled)
 {
-  nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(mStyleSheet));
+  nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(GetStyleSheet()));
   nsresult result = NS_OK;
 
   if (ss) {
diff -up mozilla/content/html/content/src/nsHTMLStyleElement.cpp.475136 mozilla/content/html/content/src/nsHTMLStyleElement.cpp
--- content/html/content/src/nsHTMLStyleElement.cpp.475136	2005-04-19 00:58:30.000000000 +0200
+++ content/html/content/src/nsHTMLStyleElement.cpp	2009-02-17 18:01:21.000000000 +0100
@@ -141,8 +141,8 @@ nsHTMLStyleElement::GetDisabled(PRBool* 
 {
   nsresult result = NS_OK;
   
-  if (mStyleSheet) {
-    nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(mStyleSheet));
+  if (GetStyleSheet()) {
+    nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(GetStyleSheet()));
 
     if (ss) {
       result = ss->GetDisabled(aDisabled);
@@ -160,8 +160,8 @@ nsHTMLStyleElement::SetDisabled(PRBool a
 {
   nsresult result = NS_OK;
   
-  if (mStyleSheet) {
-    nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(mStyleSheet));
+  if (GetStyleSheet()) {
+    nsCOMPtr<nsIDOMStyleSheet> ss(do_QueryInterface(GetStyleSheet()));
 
     if (ss) {
       result = ss->SetDisabled(aDisabled);