Index: modules/comment.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/comment.module,v
retrieving revision 1.391
diff -u -F^f -r1.391 comment.module
--- modules/comment.module	21 Nov 2005 08:32:31 -0000	1.391
+++ modules/comment.module	22 Nov 2005 12:14:41 -0000
@@ -1188,7 +1188,7 @@ function comment_form($edit, $title = NU
   }
 
   if ($op == t('Preview comment')) {
-    $form['#post_process'] = 'comment_form_add_preview';
+    $form['#after_build'] = 'comment_form_add_preview';
   }
 
   if ($_REQUEST['destination']) {