=== modified file 'compiz-plugins-main-0.9.6/wall/src/wall.cpp'
--- compiz-plugins-main-0.9.6/wall/src/wall.cpp	2011-03-14 16:07:54 +0000
+++ compiz-plugins-main-0.9.6/wall/src/wall.cpp	2011-10-11 13:28:07 +0000
@@ -608,9 +608,9 @@
 	int       dx, dy;
 	CompPoint viewport;
 
-	viewport = window->defaultViewport ();
-	dx       = viewport.x ();
-	dy       = viewport.y ();
+	screen->viewportForGeometry (window->geometry (), viewport);
+	dx       = abs(viewport.x () % screen->vpSize ().width ());
+	dy       = abs(viewport.y () % screen->vpSize ().height ());
 
 	dx -= screen->vp ().x ();
 	dy -= screen->vp ().y ();