diff -up metacity-2.21.5/src/window.h.skip-taskbar-tab metacity-2.21.5/src/window.h
--- metacity-2.21.5/src/window.h.skip-taskbar-tab	2008-02-03 01:21:30.000000000 -0500
+++ metacity-2.21.5/src/window.h	2008-02-03 01:21:34.000000000 -0500
@@ -558,7 +558,7 @@ gboolean meta_window_same_application (M
 #define META_WINDOW_IN_NORMAL_TAB_CHAIN(w) \
   (((w)->input || (w)->take_focus ) && META_WINDOW_IN_NORMAL_TAB_CHAIN_TYPE (w) && (!(w)->skip_taskbar))
 #define META_WINDOW_IN_DOCK_TAB_CHAIN(w) \
-  (((w)->input || (w)->take_focus) && ! META_WINDOW_IN_NORMAL_TAB_CHAIN_TYPE (w))
+  (((w)->input || (w)->take_focus) && (! META_WINDOW_IN_NORMAL_TAB_CHAIN_TYPE (w) || (w)->skip_taskbar))
 #define META_WINDOW_IN_GROUP_TAB_CHAIN(w, g) \
   (((w)->input || (w)->take_focus) && (!g || meta_window_get_group(w)==g))
 
