'Check the supplied email address against a list of known free
webmail domains.'

def clean_email(self):

    email_domain = self.cleaned_data[u'email'].split(u'@')[1]
    if (email_domain in self.bad_domains):
        raise forms.ValidationError(_(u'Registration    using    free    email    addresses    is    prohibited.    Please    supply    a    different    email    address.'))
    return self.cleaned_data[u'email']
