class IntRadioSelect(forms.RadioSelect):
 def render(self, name, value, attrs=None, choices=()):
   renderer
=super(IntRadioSelect,self).render(name,value,attrs,choices)
   return renderer.__unicode__()

from django.conf import settings

def smart_unicode_from_util(s): # <-  use this function to avoid 'no
module named util' error
   if not isinstance(s, basestring):
       if hasattr(s, '__unicode__'):
           s = unicode(s)
       else:
           s = unicode(str(s), settings.DEFAULT_CHARSET)
   elif not isinstance(s, unicode):
       s = unicode(s, settings.DEFAULT_CHARSET)
   return s


def IntChoiceFieldClean(self, value):
       """
       Validates that the input is in self.choices.
       """
       value = super(forms.fields.ChoiceField, self).clean(value)
       EMPTY_VALUES = (None, '')
       if value in EMPTY_VALUES:
           value = u''
       value = smart_unicode_from_util(value)
       if value == u'':
           return value
       valid_values = set([smart_unicode_from_util(k) for k, v in
self.choices])
       if value not in valid_values:
           raise ValidationError(gettext(u'Select a valid choice.
That choice is not one of the available choices.'))
       return value

forms.fields.ChoiceField.clean = IntChoiceFieldClean