Index: includes/css.inc
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/ctools/includes/css.inc,v
retrieving revision 1.15
diff -u -p -r1.15 css.inc
--- includes/css.inc	7 Sep 2010 09:02:50 -0000	1.15
+++ includes/css.inc	9 Sep 2010 15:04:19 -0000
@@ -587,7 +587,7 @@ function ctools_css_flush_caches() {
   // Remove all generated files.
   // @see http://drupal.org/node/573292
   // file_unmanaged_delete_recursive('public://render');
-  $filedir = file_directory_path('public') . '/ctools/css';
+  $filedir = file_default_scheme() . '://ctools/css';
   file_unmanaged_delete_recursive($filedir);
 
   db_delete('ctools_css_cache')->execute();