diff --git a/widget/src/gtk/nsScreenManagerGtk.cpp b/widget/src/gtk/nsScreenManagerGtk.cpp
index cf1d9cc5f62..6f9f472dc55 100644
--- a/widget/src/gtk/nsScreenManagerGtk.cpp
+++ b/widget/src/gtk/nsScreenManagerGtk.cpp
@@ -235,3 +235,8 @@ nsScreenManagerGtk :: GetNumberOfScreens(PRUint32 *aNumberOfScreens)
   
 } // GetNumberOfScreens
 
+NS_IMETHODIMP
+nsScreenManagerGtk :: ScreenForNativeWidget(void *nativeWidget, nsIScreen **aScreen)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}