diff --git a/fivestar.module b/fivestar.module
index 8831fa8..00d46ef 100644
--- a/fivestar.module
+++ b/fivestar.module
@@ -417,8 +417,7 @@ function fivestar_ajax_submit($form, $form_state) {
   $values['count'] = isset($votes['count']['value']) ? $votes['count']['value'] : 0;
 
   $form['vote']['#values'] = $values;
-  // TODO: why does passing in NULL works, yet passing in the actual form-id doesn't work.
-  drupal_process_form(NULL, $form, $form_state);
+  drupal_process_form($form['#form_id'], $form, $form_state);
 
   return array(
     '#type' => 'ajax',