Index: admin.theme.inc
--- admin.theme.inc Base (BASE)
+++ admin.theme.inc Locally Modified (Based On LOCAL)
@@ -33,6 +33,10 @@
     '#type' => 'submit',
     '#value' => t('Save configuration'),
   );
-  $form['#submit'] = array('system_settings_form_submit');
+  $form['#submit'] = array('system_settings_form_submit', 'admin_block_theme_form_submit');
   return $form;
 }
+
+function admin_block_theme_form_submit() {
+  drupal_flush_all_caches();
+}