diff --git a/layout/xul/base/src/nsMenuBarFrame.cpp b/layout/xul/base/src/nsMenuBarFrame.cpp
index 24fc3efa82d..4f8ad9a50e5 100644
--- a/layout/xul/base/src/nsMenuBarFrame.cpp
+++ b/layout/xul/base/src/nsMenuBarFrame.cpp
@@ -579,7 +579,9 @@ NS_IMETHODIMP nsMenuBarFrame::SetCurrentMenuItem(nsIMenuFrame* aMenuItem)
     aMenuItem->SelectMenu(PR_TRUE);
     aMenuItem->MarkAsGenerated(); // Have the menu building. Get it ready to be shown.
 
-    if (wasOpen)
+    PRBool isDisabled = PR_FALSE;
+    aMenuItem->MenuIsDisabled(isDisabled);
+    if (wasOpen&&!isDisabled)
       aMenuItem->OpenMenu(PR_TRUE);
   }