Index: user.pages.inc
===================================================================
--- user.pages.inc	(revision 174)
+++ user.pages.inc	(working copy)
@@ -36,8 +36,11 @@
     '#maxlength' => max(USERNAME_MAX_LENGTH, EMAIL_MAX_LENGTH),
     '#required' => TRUE,
   );
+  // Enable autocomplete
+  if (user_access('access user profiles')) {
+    $form['name']['#autocomplete_path'] = 'user/autocomplete';
+  }
   $form['submit'] = array('#type' => 'submit', '#value' => t('E-mail new password'));
-
   return $form;
 }