diff --git a/mozilla/content/html/document/src/nsHTMLDocument.cpp b/mozilla/content/html/document/src/nsHTMLDocument.cpp
index 22bdbfd6c77..cc033dec199 100644
--- a/mozilla/content/html/document/src/nsHTMLDocument.cpp
+++ b/mozilla/content/html/document/src/nsHTMLDocument.cpp
@@ -1826,21 +1826,6 @@ nsHTMLDocument::SetCookie(const nsAString& aCookie)
   return NS_OK;
 }
 
-// static
-nsIPrincipal *
-nsHTMLDocument::GetCallerPrincipal()
-{
-  // XXX This will fail on non-DOM contexts :(
-  nsIDOMDocument *domDoc = nsContentUtils::GetDocumentFromCaller();
-
-  nsCOMPtr<nsIDocument> doc(do_QueryInterface(domDoc));
-  if (!doc) {
-    return nsnull; // No document in the window
-  }
-
-  return doc->GetPrincipal();
-}
-
 // XXX TBI: accepting arguments to the open method.
 nsresult
 nsHTMLDocument::OpenCommon(const nsACString& aContentType, PRBool aReplace)
@@ -1868,7 +1853,9 @@ nsHTMLDocument::OpenCommon(const nsACString& aContentType, PRBool aReplace)
 
   if (callerDoc) {
     securityInfo = callerDoc->GetSecurityInfo();
-    callerPrincipal = GetCallerPrincipal();
+
+    nsContentUtils::GetSecurityManager()->
+      GetSubjectPrincipal(getter_AddRefs(callerPrincipal));
   }
 
   // The URI for the document after this call. Get it from the calling
diff --git a/mozilla/content/html/document/src/nsHTMLDocument.h b/mozilla/content/html/document/src/nsHTMLDocument.h
index 4d70dfca015..46b79d6e616 100644
--- a/mozilla/content/html/document/src/nsHTMLDocument.h
+++ b/mozilla/content/html/document/src/nsHTMLDocument.h
@@ -229,8 +229,6 @@ protected:
   static PRBool MatchNameAttribute(nsIContent* aContent, PRInt32 aNamespaceID,
                                    nsIAtom* aAtom, const nsAString& aData);
 
-  static nsIPrincipal *GetCallerPrincipal();
-
   static void DocumentWriteTerminationFunc(nsISupports *aRef);
 
   PRBool GetBodyContent();