=== modified file 'includes/form.inc'
--- includes/form.inc   2010-03-09 05:01:45 +0000
+++ includes/form.inc   2010-03-11 13:40:33 +0000
@@ -481,10 +481,6 @@
   // Programmed forms are always submitted.
   $form_state['submitted'] = TRUE;
 
-  // Reset form validation.
-  $form_state['must_validate'] = TRUE;
-  form_clear_error();
-
   drupal_prepare_form($form_id, $form, $form_state);
   drupal_process_form($form_id, $form, $form_state);
 }
@@ -781,12 +777,6 @@
  *   not be repeated in the submission step.
  */
 function drupal_validate_form($form_id, &$form, &$form_state) {
-  $validated_forms = &drupal_static(__FUNCTION__, array());
-
-  if (isset($validated_forms[$form_id]) && empty($form_state['must_validate'])) {
-    return;
-  }
-
   // If the session token was set by drupal_prepare_form(), ensure that it
   // matches the current user's session.
   if (isset($form['#token'])) {
@@ -797,7 +787,6 @@
   }
 
   _form_validate($form, $form_state, $form_id);
-  $validated_forms[$form_id] = TRUE;
 }
 
 /**