? user.patch
Index: user.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/user/user.module,v
retrieving revision 1.1000
diff -u -p -r1.1000 user.module
--- user.module	8 Jun 2009 05:00:11 -0000	1.1000
+++ user.module	13 Jun 2009 14:35:21 -0000
@@ -618,7 +618,7 @@ function user_validate_mail($mail) {
   if (!$mail) {
     return t('You must enter an e-mail address.');
   }
-  if (!valid_email_address($mail)) {
+  if (!valid_email_address(trim ($mail))) {
     return t('The e-mail address %mail is not valid.', array('%mail' => $mail));
   }
 }
@@ -2767,7 +2767,7 @@ function user_register_submit($form, &$f
   global $base_url;
   $admin = user_access('administer users');
 
-  $mail = $form_state['values']['mail'];
+  $mail = $form_state['values']['mail'] = trim ($form_state['values']['mail']);
   $name = $form_state['values']['name'];
   if (!variable_get('user_email_verification', TRUE) || $admin) {
     $pass = $form_state['values']['pass'];