Index: includes/form.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/form.inc,v
retrieving revision 1.265.2.23
diff -u -p -r1.265.2.23 form.inc
--- includes/form.inc	27 Apr 2009 14:41:11 -0000	1.265.2.23
+++ includes/form.inc	26 May 2009 20:01:47 -0000
@@ -294,6 +294,10 @@ function drupal_execute($form_id, &$form
   $args = func_get_args();
   $form = call_user_func_array('drupal_retrieve_form', $args);
   $form['#post'] = $form_state['values'];
+  // Reset form validation.
+  // If form validation fails once it fails for all subsequent elements!
+  $form_state['must_validate'] = TRUE;
+  form_set_error(NULL, '', TRUE);  // reset all form errors
   drupal_prepare_form($form_id, $form, $form_state);
   drupal_process_form($form_id, $form, $form_state);
 }
@@ -561,12 +565,6 @@ function drupal_prepare_form($form_id, &
  *   not be repeated in the submission step.
  */
 function drupal_validate_form($form_id, $form, &$form_state) {
-  static $validated_forms = array();
-
-  if (isset($validated_forms[$form_id])) {
-    return;
-  }
-
   // If the session token was set by drupal_prepare_form(), ensure that it
   // matches the current user's session.
   if (isset($form['#token'])) {
@@ -577,7 +575,6 @@ function drupal_validate_form($form_id, 
   }
 
   _form_validate($form, $form_state, $form_id);
-  $validated_forms[$form_id] = TRUE;
 }
 
 /**