Index: cas.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/cas/cas.module,v
retrieving revision 1.61
diff -u -p -r1.61 cas.module
--- cas.module  10 Nov 2009 16:17:48 -0000      1.61
+++ cas.module  14 Jan 2010 19:41:01 -0000
@@ -798,6 +798,10 @@ function cas_logout() {
     $logout_destination .= '?destination='. $destination .'&service='. $destination .'&url='. $destination;
   }
   
+  // Remove our original destination from the request array so that it won't cause
+  // drupal_goto to re-write the url.
+  unset($_REQUEST['destination']);
+  
   // Go to the constructed logout destination
   drupal_goto($logout_destination);
 }