Index: modules/aggregator/aggregator.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/aggregator/aggregator.admin.inc,v
retrieving revision 1.27
diff -u -p -r1.27 aggregator.admin.inc
--- modules/aggregator/aggregator.admin.inc	13 May 2009 19:38:28 -0000	1.27
+++ modules/aggregator/aggregator.admin.inc	16 May 2009 23:04:18 -0000
@@ -479,7 +479,10 @@ function aggregator_admin_form($form_sta
 }
 
 function aggregator_admin_form_submit($form, &$form_state) {
-  $form_state['values']['aggregator_processors'] = array_filter($form_state['values']['aggregator_processors']);
+  $processors = module_implements('aggregator_process');
+  if (count($processors) > 1) {
+    $form_state['values']['aggregator_processors'] = array_filter($form_state['values']['aggregator_processors']);
+  }
   system_settings_form_submit($form, $form_state);
 }