diff --git a/ChangeLog b/ChangeLog
index 97fba5c36..a0748c913 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2008-04-22  Carlos Garnacho  <carlos@imendio.com>
+
+        * src/core/compositor.c (process_property_notify,
+        find_window_in_display): Propagate opacity to frame window.
+
 2008-04-22  Thomas Thurman  <tthurman@gnome.org>
 
         * configure.in: Post-release bump to 2.23.13.
diff --git a/src/core/compositor.c b/src/core/compositor.c
index c37a78189..4c44a6f04 100644
--- a/src/core/compositor.c
+++ b/src/core/compositor.c
@@ -645,6 +645,24 @@ find_window_in_display (MetaDisplay *display,
   return NULL;
 }
 
+static MetaCompWindow *
+find_window_for_child_window_in_display (MetaDisplay *display,
+                                         Window       xwindow)
+{
+  Window ignored1, *ignored2;
+  Window parent;
+  guint ignored_children;
+
+  XQueryTree (display->xdisplay,
+              xwindow, &ignored1, &parent,
+              &ignored2, &ignored_children);
+
+  if (parent != None)
+    return find_window_in_display (display, parent);
+
+  return NULL;
+}
+
 static Picture
 solid_picture (MetaDisplay *display,
                MetaScreen  *screen,
@@ -2117,7 +2135,15 @@ process_property_notify (MetaCompositor *compositor,
       MetaCompWindow *cw = find_window_in_display (display, event->window);
       gulong value;
 
-      if (!cw) 
+      if (!cw)
+        {
+          /* Applications can set this property for their toplevel windows, so
+           * this must be propagated to the window managed by the compositor
+           */
+          cw = find_window_for_child_window_in_display (display, event->window);
+        }
+
+      if (!cw)
         return;
 
       if (meta_prop_get_cardinal (display, event->window,