diff --git a/resources/inc/class.bo_acl.inc.php b/resources/inc/class.bo_acl.inc.php
index bf49b2236b..1fa0598b79 100755
--- a/resources/inc/class.bo_acl.inc.php
+++ b/resources/inc/class.bo_acl.inc.php
@@ -108,7 +108,7 @@ class bo_acl
 				$perm_cats[$cat['id']] = $s;
 			}
 		}
-		return $perm_cats;
+		return isset($perm_cats)?$perm_cats:array();
 	}