Index: django/db/models/fields/__init__.py
===================================================================
--- django/db/models/fields/__init__.py	(revision 5065)
+++ django/db/models/fields/__init__.py	(working copy)
@@ -732,6 +732,11 @@
         kwargs['maxlength'] = 15
         Field.__init__(self, *args, **kwargs)
 
+    def formfield(self, **kwargs):
+        defaults = {'required': not self.blank, 'label': capfirst(self.verbose_name), 'help_text': self.help_text}
+        defaults.update(kwargs)
+        return forms.RegexField(validators.ip4_re, **defaults)
+
     def get_manipulator_field_objs(self):
         return [oldforms.IPAddressField]