diff --git a/mozilla/layout/xul/base/src/nsScrollbarFrame.cpp b/mozilla/layout/xul/base/src/nsScrollbarFrame.cpp
index f46a2cbc08e..3241b294579 100644
--- a/mozilla/layout/xul/base/src/nsScrollbarFrame.cpp
+++ b/mozilla/layout/xul/base/src/nsScrollbarFrame.cpp
@@ -207,8 +207,8 @@ nsresult NS_CreateAnonymousNode(nsIContent* aParent, nsIAtom* aTag, PRInt32 aNam
 {
 
     // get the document
-    nsIDocument* document = nsnull;
-    aParent->GetDocument(document);
+    nsCOMPtr<nsIDocument> document;
+    aParent->GetDocument(*getter_AddRefs(document));
     
     // create the xml element
     nsCOMPtr<nsIXMLContent> content;