I believe that Karl Nelson submitted a patch for this towards the end of
2000, but it isn't in the current release or CVS, and I can't find his
original posting:

Language-bindings that use the BUILDER_DATA UIInfo items will have
disappearing menus in their MDI apps. Apparently it is fixed if
count_ui_info_items() is changed slightly to read:


static gint count_ui_info_items (const GnomeUIInfo *ui_info)
   {
   gint num;
   gint count=0;

   for(num = 0; ui_info[num].type != GNOME_APP_UI_ENDOFINFO; num++)
   if (ui_info[num].type != GNOME_APP_UI_HELP && 
   ui_info[num].type != GNOME_APP_UI_BUILDER_DATA)
   count++;

   return count;
   }

I'd submit a real patch, but I can't figure out how to checkout the stable
branch. I have checked HEAD, and this needs to be done there too.