Index: trunk/wb/admin/pages/add.php
===================================================================
--- trunk/wb/admin/pages/add.php	(revision 737)
+++ trunk/wb/admin/pages/add.php	(revision 738)
@@ -41,7 +41,9 @@
 $viewing_groups = $admin->get_post('viewing_groups');
 
 // work-around: $viewing_groups contains group-numbers for both private _and_ registered - keep group-numbers which appears twice only
-$view_groups=array(); 
+$view_groups=array();
+if($viewing_groups===NULL)
+	$viewing_groups=array();
 foreach($viewing_groups as $a) {
 	if(isset($view_groups[$a])) $view_groups[$a]++;
 	else $view_groups[$a] = 1;