diff -Nur metacity-2.12.1.orig/src/place.c metacity-2.12.1/src/place.c
--- metacity-2.12.1.orig/src/place.c	2005-09-29 17:53:52.000000000 +0200
+++ metacity-2.12.1/src/place.c	2006-03-11 16:57:43.000000000 +0100
@@ -921,6 +921,8 @@
   x = xi->x_origin;
   y = xi->y_origin;
 
+  n_xineramas = 1;
+
   if (find_first_fit (window, fgeom, windows,
                       xineramas_list, n_xineramas,
                       x, y, &x, &y))