Index: db/models/fields/__init__.py
===================================================================
--- db/models/fields/__init__.py	(revision 17904)
+++ db/models/fields/__init__.py	(working copy)
@@ -627,6 +627,31 @@
         defaults.update(kwargs)
         return super(CharField, self).formfield(**defaults)
 
+class DomainNameField(CharField):
+    """An Internationalized Domain Name in ASCII or UTF format, stored as idna-encoded (ASCII) string."""
+    description = _("Internet Domain Name")
+
+    def __init__(self, *args, **kwargs):
+        accept_idna = kwargs.pop('accept_idna', True)
+        kwargs['max_length'] = 255
+        super(CharField, self).__init__(*args, **kwargs)
+        self.validators.append(validators.DomainNameValidator(accept_idna=accept_idna))
+
+    def to_python(self, value):
+        # we always store domain names in ASCII format
+        value = super(DomainNameField, self).to_python(value)
+        # make sure we got called on RAW data, because django calls to_python()
+        # even on already-python data. IDNA-decoding UTF would raise exception.
+        if value.encode('idna') != value:   # value is UTF (python) already
+            return value
+        # value is RAW or python-ASCII, safe to encode in either case
+        return value.decode('idna')
+
+    def get_prep_value(self, value):
+        # we always store domain names in ASCII format
+        return value.encode('idna')
+
+
 # TODO: Maybe move this into contrib, because it's specialized.
 class CommaSeparatedIntegerField(CharField):
     default_validators = [validators.validate_comma_separated_integer_list]