diff --git a/Classes/DataHandler/AbstractDataHandler.php b/Classes/DataHandler/AbstractDataHandler.php
index 30ba225..c994f79 100644
--- a/Classes/DataHandler/AbstractDataHandler.php
+++ b/Classes/DataHandler/AbstractDataHandler.php
@@ -243,8 +243,8 @@ public function checkAndUpdateTranslatedElements($uid)
             if ($translatedElement['tx_gridelements_container'] !== $updateArray['tx_gridelements_container']) {
                 $containerUpdateArray[$translatedElement['tx_gridelements_container']] -= 1;
                 $containerUpdateArray[$updateArray['tx_gridelements_container']] += 1;
-                $this->getTceMain()->updateRefIndex('tt_content', $translatedElement['tx_gridelements_container']);
-                $this->getTceMain()->updateRefIndex('tt_content', $updateArray['tx_gridelements_container']);
+                $this->getTceMain()->updateRefIndex('tt_content', (int)$translatedElement['tx_gridelements_container']);
+                $this->getTceMain()->updateRefIndex('tt_content', (int)$updateArray['tx_gridelements_container']);
             }
         }
         if (!empty($containerUpdateArray)) {