--- xcompmgr-1.1.5/xcompmgr.c	2009-10-20 00:44:23.000000000 +0200
+++ xcompmgr-local/xcompmgr.c	2010-03-16 09:31:00.082699594 +0100
@@ -1023,6 +1023,7 @@
 	{
 	    w->borderClip = XFixesCreateRegion (dpy, NULL, 0);
 	    XFixesCopyRegion (dpy, w->borderClip, region);
+	    XFixesIntersectRegion(dpy, w->borderClip, w->borderClip, w->borderSize);
 	}
 	w->prev_trans = t;
 	t = w;