diff --git a/modules/update/update.module b/modules/update/update.module
index 20f148b7dd5e..92c541469603 100644
--- a/modules/update/update.module
+++ b/modules/update/update.module
@@ -293,7 +293,7 @@ function update_cron() {
  *
  * @see _update_cache_clear()
  */
-function update_form_system_themes_alter(&$form, $form_state) {
+function update_form_system_themes_form_alter(&$form, $form_state) {
   $form['#submit'][] = 'update_cache_clear_submit';
 }