diff --git a/wxPython/src/_mdi.i b/wxPython/src/_mdi.i
index d2791fe1b6..9264b85389 100644
--- a/wxPython/src/_mdi.i
+++ b/wxPython/src/_mdi.i
@@ -76,7 +76,7 @@ public:
     void SetWindowMenu(wxMenu* menu);
     void SetToolBar(wxToolBar* toolbar);
 #endif
-    void Tile();
+    void Tile(wxOrientation orient = wxHORIZONTAL);
 };
 
 //---------------------------------------------------------------------------