Unicode fix reverted but can have custom validator

MongoEngine/mongoengine#136

tests/test_fields.py

@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 from __future__ import with_statement
 import datetime
 import os
@@ -199,9 +200,6 @@ class FieldTest(unittest.TestCase):
         link.url = 'http://www.google.com:8080'
         link.validate()
 
-        link.url = u'http://президент.рф'
-        self.assertTrue(link.validate())
-
     def test_int_validation(self):
         """Ensure that invalid values cannot be assigned to int fields.
         """