Index: muffin/src/core/keybindings.c
===================================================================
--- muffin.orig/src/core/keybindings.c	2014-07-12 11:14:43.726606468 +0200
+++ muffin/src/core/keybindings.c	2014-10-25 19:43:34.635326714 +0200
@@ -1639,6 +1639,15 @@
   else if (event->xkey.type == KeyPress &&
            event->xkey.keycode == display->overlay_key_combo.keycode)
     {
+      /* Check if the mask also matches */
+      unsigned int combo_mask;
+      meta_display_devirtualize_modifiers (display,
+                                           display->overlay_key_combo.modifiers,
+                                           &combo_mask);
+      unsigned int event_mask = event->xkey.state & 0xff &
+                                ~display->ignored_modifier_mask;
+      if (event_mask != combo_mask) return FALSE;
+
       display->overlay_key_only_pressed = TRUE;
       /* We keep the keyboard frozen - this allows us to use ReplayKeyboard
        * on the next event if it's not the release of the overlay key */
@@ -1675,7 +1684,6 @@
   gboolean handled;
   const char *str;
   MetaScreen *screen;
-
   if (all_bindings_disabled)
     {
       /* In this mode, we try to pretend we don't have grabs, so we