Eu tenho alguns modelos de django para o meu perfil de usuários estendidos. O problema é que esse código não cria tabelas quando o syncdb é usado (simplesmente nada acontece. Sem erros de validação). Por que isso está acontecendo? (Esses modelos também fornecem erro de importação em outro lugar):

#!/usr/bin/env python
# encoding: utf-8
from django.db import models
from django.contrib.auth.models import User
from registration.signals import user_registered
from forms import ExtendedRegistrationForm
import hashlib

class InheritedProfile(models.Model):
    first_name = models.CharField("Name", max_length=50, blank=True, null=True)
    last_name = models.CharField("Last name", max_length=50, blank=True, null=True)
    pid = models.CharField("PESEL", max_length=11, blank=True, null=True)
    street = models.CharField("Street", max_length=50, blank=True, null=True)
    number = models.CharField("Flat/house number", max_length=10, blank=True, null=True)
    code = models.CharField("Zip ", max_length=6, blank=True, null=True)
    city = models.CharField("City", max_length=50, blank=True, null=True) 
    class Meta:
        abstract=True

class UserProfile(InheritedProfile):
    def upload_path(self, field_attname):
        filename = hashlib.md5(field_attname).hexdigest()[:4] + "_" + field_attname
        return "uploads/users/%s" % (filename,)

    user = models.ForeignKey(User, unique=True, related_name='profile')
    image = models.ImageField(upload_to=upload_path, verbose_name="Image", blank=True, null=True)

    class Meta:
        ordering = ['-id']
        db_table = 'userprofile'

    def __unicode__(self):
        return u"%s " % self.user.username

def user_created(sender, user, request, **kwargs):
    form = ExtendedRegistrationForm(request.POST)
    extended_user = UserProfile(user=user)
    extended_user.is_active = False
    extended_user.first_name = form.cleaned_data['first_name']
    extended_user.last_name = form.cleaned_data['last_name']
    extended_user.pid = form.cleaned_data['pid']
    extended_user.image = form.cleaned_data['image']
    extended_user.street = form.cleaned_data['street']
    extended_user.number = form.cleaned_data['number']
    extended_user.code = form.cleaned_data['code']
    extended_user.city = form.cleaned_data['city']
    extended_user.save()

user_registered.connect(user_created)

class Friend(InheritedProfile):
    friend_of = models.ForeignKey(UserProfile, related_name='friend_of')
    class Meta:
        db_table = 'friend'

Pelo contrário, este código produz tabelas sem falhas:

#!/usr/bin/env python
# encoding: utf-8
from django.db import models
from django.contrib.auth.models import User
import hashlib

class InheritedProfile(models.Model):
    first_name = models.CharField("Name", max_length=50, blank=True, null=True)
    last_name = models.CharField("Last name", max_length=50, blank=True, null=True)
    pid = models.CharField("PESEL", max_length=11, blank=True, null=True)
    street = models.CharField("Street", max_length=50, blank=True, null=True)
    number = models.CharField("Flat/house number", max_length=10, blank=True, null=True)
    code = models.CharField("Zip ", max_length=6, blank=True, null=True)
    city = models.CharField("City", max_length=50, blank=True, null=True) 
    class Meta:
        abstract=True

class UserProfile(InheritedProfile):
    def upload_path(self, field_attname):
        filename = hashlib.md5(field_attname).hexdigest()[:4] + "_" + field_attname
        return "uploads/users/%s" % (filename,)

    user = models.ForeignKey(User, unique=True, related_name='profile')
    image = models.ImageField(upload_to=upload_path, verbose_name="Image", blank=True, null=True)

    class Meta:
        ordering = ['-id']
        db_table = 'userprofile'

    def __unicode__(self):
        return u"%s " % self.user.username

class Friend(InheritedProfile):
    friend_of = models.ForeignKey(UserProfile, related_name='friend_of')
    class Meta:
        db_table = 'friend'

Devo mover essa função user_created para outro lugar? Os sinais não devem criar problemas aqui ...