diff --git apachesolr_multilingual.module apachesolr_multilingual.module
index b0968fe..6bbe0c2 100644
--- apachesolr_multilingual.module
+++ apachesolr_multilingual.module
@@ -410,7 +410,7 @@ function apachesolr_multilingual_form_search_form_alter(&$form, $form_state) {
         '#default_value' => isset($_GET['detach-auto-language-filter']),
       );
 
-      $form['#submit'] = array_merge(array('apachesolr_multilingual_form_search_submit'), $form['#submit']);
+      $form['#submit'][] = 'apachesolr_multilingual_form_search_submit';
     }
   }
 }