=== modified file 'includes/form.inc'
--- includes/form.inc	2009-02-03 18:55:29 +0000
+++ includes/form.inc	2009-03-02 05:27:34 +0000
@@ -139,7 +139,7 @@ function drupal_get_form($form_id) {
   // the form, passing in the latest $form_state in addition to any
   // other variables passed into drupal_get_form().
 
-  if (!empty($form_state['rebuild']) || !empty($form_state['storage'])) {
+  if (!form_get_errors() && (!empty($form_state['rebuild']) || !empty($form_state['storage']))) {
     $form = drupal_rebuild_form($form_id, $form_state, $args);
   }
 
@@ -1972,7 +1972,7 @@ function theme_checkboxes($element) {
     $class .= ' ' . $element['#attributes']['class'];
   }
   $element['#children'] = '<div class="' . $class . '">' . (!empty($element['#children']) ? $element['#children'] : '') . '</div>';
-  
+
   return $element['#children'];
 }