Index: modules/system/system.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.module,v
retrieving revision 1.585.2.19
diff -u -p -r1.585.2.19 system.module
--- modules/system/system.module	5 Sep 2008 09:29:23 -0000	1.585.2.19
+++ modules/system/system.module	30 Sep 2008 07:19:14 -0000
@@ -1049,16 +1049,17 @@ function system_settings_form($form) {
  */
 function system_settings_form_submit($form, &$form_state) {
   $op = isset($form_state['values']['op']) ? $form_state['values']['op'] : '';
+  $array_filter = isset($form_state['values']['array_filter']);
 
   // Exclude unnecessary elements.
-  unset($form_state['values']['submit'], $form_state['values']['reset'], $form_state['values']['form_id'], $form_state['values']['op'], $form_state['values']['form_token'], $form_state['values']['form_build_id']);
+  unset($form_state['values']['submit'], $form_state['values']['reset'], $form_state['values']['form_id'], $form_state['values']['op'], $form_state['values']['form_token'], $form_state['values']['form_build_id'], $form_state['values']['array_filter']);
 
   foreach ($form_state['values'] as $key => $value) {
     if ($op == t('Reset to defaults')) {
       variable_del($key);
     }
     else {
-      if (is_array($value) && isset($form_state['values']['array_filter'])) {
+      if (is_array($value) && $array_filter) {
         $value = array_keys(array_filter($value));
       }
       variable_set($key, $value);