diff --git a/mozilla/rdf/datasource/src/nsXULContentSink.cpp b/mozilla/rdf/datasource/src/nsXULContentSink.cpp
index f939a666129..ee07be2cb4b 100644
--- a/mozilla/rdf/datasource/src/nsXULContentSink.cpp
+++ b/mozilla/rdf/datasource/src/nsXULContentSink.cpp
@@ -813,8 +813,11 @@ XULContentSinkImpl::ProcessOverlay(const nsString& aHref)
       return result;
   }
 
-  docLoader->LoadSubDocument(aHref,
-                             docInfo.get());
+  nsCOMPtr<nsIURI> uri;
+  result = NS_NewURI(getter_AddRefs(uri), aHref, mDocumentBaseURL);
+  if (NS_FAILED(result)) return result;
+
+  return docLoader->LoadSubDocument(uri, docInfo.get());
   return result;
 }
 
diff --git a/mozilla/webshell/public/nsIDocumentLoader.h b/mozilla/webshell/public/nsIDocumentLoader.h
index 92c44b04981..0a879e3778d 100644
--- a/mozilla/webshell/public/nsIDocumentLoader.h
+++ b/mozilla/webshell/public/nsIDocumentLoader.h
@@ -102,26 +102,18 @@ class nsIDocumentLoader : public nsISupports
 public:
     NS_DEFINE_STATIC_IID_ACCESSOR(NS_IDOCUMENTLOADER_IID)
 
-    NS_IMETHOD LoadDocument(const nsString& aURLSpec, 
+    NS_IMETHOD LoadDocument(nsIURI * aUri, 
                             const char* aCommand,
                             nsIContentViewerContainer* aContainer,
                             nsIInputStream* aPostDataStream = nsnull,
                             nsISupports* aExtraInfo = nsnull,
                             nsIStreamObserver* anObserver = nsnull,
-#ifdef NECKO
                             nsLoadFlags aType = nsIChannel::LOAD_NORMAL,
-#else
-                            nsURLReloadType aType = nsURLReload,
-#endif
                             const PRUint32 aLocalIP = 0) = 0;
 
-    NS_IMETHOD LoadSubDocument(const nsString& aURLSpec,
+    NS_IMETHOD LoadSubDocument(nsIURI * aUri,
                                nsISupports* aExtraInfo = nsnull,
-#ifdef NECKO
                                nsLoadFlags aType = nsIChannel::LOAD_NORMAL,
-#else
-                               nsURLReloadType aType = nsURLReload,
-#endif
                                const PRUint32 aLocalIP = 0) = 0;
 
     NS_IMETHOD Stop(void) = 0;