diff --git a/message.module b/message.module
index bd44e02..6632ebd 100644
--- a/message.module
+++ b/message.module
@@ -455,7 +455,7 @@ function message_entity_delete($entity, $entity_type) {
  */
 function message_get_purgeable_by_type(&$purge_limit, $message_type_name, $purge_settings) {
   if ($purge_limit <= 0) {
-    return;
+    return array();
   }
 
   // Messages to be deleted.