Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.477
diff -u -p -r1.477 form.inc
--- includes/form.inc	10 Jul 2010 00:03:37 -0000	1.477
+++ includes/form.inc	13 Jul 2010 15:59:25 -0000
@@ -1587,16 +1587,6 @@ function form_builder($form_id, $element
 
     // Special processing if the triggering element is a button.
     if (isset($form_state['triggering_element']['#button_type'])) {
-      // Because there are several ways in which the triggering element could
-      // have been determined (including from input variables set by JavaScript
-      // or fallback behavior implemented for IE), and because buttons often
-      // have their #name property not derived from their #parents property, we
-      // can't assume that input processing that's happened up until here has
-      // resulted in $form_state['values'][BUTTON_NAME] being set. But it's
-      // common for forms to have several buttons named 'op' and switch on
-      // $form_state['values']['op'] during submit handler execution.
-      $form_state['values'][$form_state['triggering_element']['#name']] = $form_state['triggering_element']['#value'];
-
       // @todo Legacy support. Remove in Drupal 8.
       $form_state['clicked_button'] = $form_state['triggering_element'];
     }
Index: modules/system/system.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.module,v
retrieving revision 1.946
diff -u -p -r1.946 system.module
--- modules/system/system.module	7 Jul 2010 17:56:42 -0000	1.946
+++ modules/system/system.module	13 Jul 2010 15:57:43 -0000
@@ -310,7 +310,6 @@ function system_element_info() {
   // Input elements.
   $types['submit'] = array(
     '#input' => TRUE,
-    '#name' => 'op',
     '#button_type' => 'submit',
     '#executes_submit_callback' => TRUE,
     '#limit_validation_errors' => FALSE,
@@ -319,7 +318,6 @@ function system_element_info() {
   );
   $types['button'] = array(
     '#input' => TRUE,
-    '#name' => 'op',
     '#button_type' => 'submit',
     '#executes_submit_callback' => FALSE,
     '#limit_validation_errors' => FALSE,
