diff --git a/wxPython/src/_defs.i b/wxPython/src/_defs.i
index e0ac91e9d4..50ebb62c98 100644
--- a/wxPython/src/_defs.i
+++ b/wxPython/src/_defs.i
@@ -492,6 +492,7 @@ enum {
     wxEXPAND,
 
     wxNB_FIXEDWIDTH,
+    wxNB_TOP,
     wxNB_LEFT,
     wxNB_RIGHT,
     wxNB_BOTTOM,