diff --git a/js/content_lock_init.js b/js/content_lock_init.js
index 1886afd..6cf000c 100644
--- a/js/content_lock_init.js
+++ b/js/content_lock_init.js
@@ -30,7 +30,7 @@ Drupal.behaviors.content_lock = {
     jQuery().onUserExit( {
       execute: content_lock_onleave,
       executeConfirm: content_lock_confirm,
-      internalURLs: Drupal.settings.content_lock.internal_urls
+      internalURLs: (typeof Drupal.settings.content_lock.internal_urls === "string") ? Drupal.settings.content_lock.internal_urls : Drupal.settings.content_lock.internal_urls.join("|")
     });
   }
 };