Index: branches/unlabeled/unlabeled-1.12.2/core/units/categories/categories_item.php
===================================================================
diff -u -N -r7640 -r7755
--- branches/unlabeled/unlabeled-1.12.2/core/units/categories/categories_item.php	(.../categories_item.php)	(revision 7640)
+++ branches/unlabeled/unlabeled-1.12.2/core/units/categories/categories_item.php	(.../categories_item.php)	(revision 7755)
@@ -75,7 +75,8 @@
 
 		function checkFilename()
 		{
-			if( !$this->GetDBField('AutomaticFilename') )
+			// System templates allow any characters in filename, because they may and will contain "/"
+			if( !$this->GetDBField('AutomaticFilename') && !$this->GetDBField('IsSystem'))
 			{
 				$filename = $this->GetDBField('Filename');
 				$this->SetDBField('Filename', $this->stripDisallowed($filename) );