diff --git a/web/skins/classic/views/js/montagereview.js.php b/web/skins/classic/views/js/montagereview.js.php
index 5d43364e7..d82f103ed 100644
--- a/web/skins/classic/views/js/montagereview.js.php
+++ b/web/skins/classic/views/js/montagereview.js.php
@@ -3,7 +3,7 @@ var server_utc_offset = <?php
 $tz = ini_get('date.timezone');
 if (!$tz) {
   $tz = 'UTC';
-  Warning('Timezone has not been set. Either select it in Options->System->Timezone or in php.ini');
+  ZM\Warning('Timezone has not been set. Either select it in Options->System->Timezone or in php.ini');
 }
 
 $TimeZone = new DateTimeZone($tz);