diff --git a/viddler.module b/viddler.module
index d350f0f..9f9ba92 100644
--- a/viddler.module
+++ b/viddler.module
@@ -94,7 +94,9 @@ function viddler_upload_js($type_name, $field_name, $delta) {
     '#post' => $_POST,
     '#programmed' => FALSE,
   );
-  drupal_alter('form', $form, array(), 'viddler_upload_js');
+  $form_state_alter = array();
+  $data = array('__drupal_alter_by_ref' => array(&$form, &$form_state_alter));
+  drupal_alter('form', $data, 'viddler_upload_js');
   $form = form_builder('viddler_upload_js', $form, $built_form_state);
   $field_form = empty($group_name) ? $form[$field_name] : $form[$group_name][$field_name];