=== modified file 'drupal/modules/user/user.module'
--- drupal/modules/user/user.module	2008-02-14 07:57:20 +0000
+++ drupal/modules/user/user.module	2008-02-27 22:46:59 +0000
@@ -2400,7 +2400,7 @@
     unset($form['account']);
   }
   else {
-    $form = array_merge($form, $extra);
+    $form = array_merge_recursive($form, $extra);
   }
 
   if (variable_get('configurable_timezones', 1)) {