Имея унаследованную модель
class ExtendetUser(User): active = models.NullBooleanField() active_link = models.CharField(max_length=20, verbose_name=u'Ключ активации', blank=True)
И следующую форму:
class MExtendetUserForm(ModelForm): username = forms.CharField(max_length=30, label = u'Никнейм', required = False) first_name = forms.CharField(max_length=30, label = u'Имя', required = False) last_name = forms.CharField(max_length=30, label = u'Фамилия', required = False) email = forms.EmailField(label = u'Email', required = False) class Meta: model = ExtendetUser fields = ('first_name', 'last_name', 'email')
При стандартной подстановке
user = ExtendetUser.objects.get(id=1) form = MExtendetUserForm(instance=user)
А form.errors говорит {}.