diff --git a/django/core/validators.py b/django/core/validators.py
index c5e7c23afb..4b9ab1f602 100644
--- a/django/core/validators.py
+++ b/django/core/validators.py
@@ -95,7 +95,7 @@ validate_comma_separated_integer_list = RegexValidator(comma_separated_int_list_
 
 
 class BaseValidator(object):
-    compare = lambda self, a, b: a is b
+    compare = lambda self, a, b: a is not b
     clean   = lambda self, x: x
     message = _(u'Ensure this value is %(limit_value)s (it is %(show_value)s).')
     code = 'limit_value'
@@ -105,11 +105,12 @@ class BaseValidator(object):
 
     def __call__(self, value):
         cleaned = self.clean(value)
+        params = {'limit_value': self.limit_value, 'show_value': cleaned}
         if self.compare(cleaned, self.limit_value):
             raise ValidationError(
-                self.message,
+                self.message % params,
                 code=self.code,
-                params={'limit_value': self.limit_value, 'show_value': cleaned}
+                params=params,
             )
 
 class MaxValueValidator(BaseValidator):
diff --git a/tests/modeltests/validators/tests.py b/tests/modeltests/validators/tests.py
index 3e185d1fc6..de4d94f1af 100644
--- a/tests/modeltests/validators/tests.py
+++ b/tests/modeltests/validators/tests.py
@@ -2,14 +2,16 @@
 import types
 from unittest import TestCase
 from datetime import datetime, timedelta
+import re
 
 from django.core.exceptions import ValidationError
 from django.core.validators import (
         validate_integer, validate_email, validate_slug, validate_ipv4_address,
         validate_comma_separated_integer_list, MaxValueValidator,
         MinValueValidator, MaxLengthValidator, MinLengthValidator,
-        RequiredIfOtherFieldBlank,
-    )
+        RequiredIfOtherFieldBlank, URLValidator, BaseValidator,
+        RegexValidator,
+)
 
 now = datetime.now()
 class TestSimpleValidators(TestCase):
@@ -94,8 +96,40 @@ SIMPLE_VALIDATORS_VALUES = (
 
     (MinLengthValidator(10), '', ValidationError),
 
+    (URLValidator(), 'http://www.djangoproject.com/', None),
+    (URLValidator(), 'http://localhost/', None),
+    (URLValidator(), 'http://example.com/', None),
+    (URLValidator(), 'http://www.example.com/', None),
+    (URLValidator(), 'http://www.example.com:8000/test', None),
+    (URLValidator(), 'http://valid-with-hyphens.com/', None),
+    (URLValidator(), 'http://subdomain.domain.com/', None),
+    (URLValidator(), 'http://200.8.9.10/', None),
+    (URLValidator(), 'http://200.8.9.10:8000/test', None),
+    (URLValidator(), 'http://valid-----hyphens.com/', None),
+
+    (URLValidator(), 'foo', ValidationError),
+    (URLValidator(), 'http://', ValidationError),
+    (URLValidator(), 'http://example', ValidationError),
+    (URLValidator(), 'http://example.', ValidationError),
+    (URLValidator(), 'http://.com', ValidationError),
+    (URLValidator(), 'http://invalid-.com', ValidationError),
+    (URLValidator(), 'http://-invalid.com', ValidationError),
+    (URLValidator(), 'http://inv-.alid-.com', ValidationError),
+    (URLValidator(), 'http://inv-.-alid.com', ValidationError),
+
+    (BaseValidator(True), True, None),
+    (BaseValidator(True), False, ValidationError),
+
+    (RegexValidator('.*'), '', None),
+    (RegexValidator(re.compile('.*')), '', None),
+    (RegexValidator('.*'), 'xxxxx', None),
+
+    (RegexValidator('x'), 'y', ValidationError),
+    (RegexValidator(re.compile('x')), 'y', ValidationError),
+
 )
 
+
 def get_simple_test_func(validator, expected, value, num):
     if isinstance(expected, type) and issubclass(expected, Exception):
         test_mask = 'test_%s_raises_error_%d'