Django (Python) : DatabaseError : x Table has No Column named y

hi i am working on a django python application using sqlite3 database. I have a an extention to django’s user model defined in my models.py as follows:

#Account Model
class Account(models.Model):
  user = models.OneToOneField(User)
  avatar_url = models.CharField(max_length=200)
  profile_url = models.CharField(max_length=200)
  account_type = models.CharField(max_length=60, choices=choices.ACCOUNT_TYPE)

i also have a method to create the Account object and a post_save handler defined like this:

#Function to Create user Account/Profile
def create_user_account(sender, instance, created, **kwargs):
  if created:
    models.Account.objects.create(user=instance)

#Create User / User Registration
def UserRegistration(request):
  if request.method == 'POST':
    username = request.POST['fn'].capitalize() + ' ' + request.POST['ln'].capitalize()
    # CREATE USER
    newuser = User.objects.create_user(username=username,
                                       email=request.POST['email'],
                                       password=request.POST['pw'])
    newuser.save()
  return HttpResponse(username)

#Post Save handler to create user Account/Profile
post_save.connect(create_user_account, sender=User)

Now, whenever i try to register a new user i get the following database error:

DatabaseError at /register/

table engine_account has no column named user_id

Request Method:     POST
Request URL:    http://localhost:8000/register/
Django Version:     1.4
Exception Type:     DatabaseError
Exception Value:    

table engine_account has no column named user_id

Exception Location:     /usr/local/lib/python2.7/dist-packages/Django-1.4-py2.7.egg/django/db/backends/sqlite3/base.py in execute, line 337
Python Executable:  /usr/bin/python
Python Version:     2.7.3

and i have no idea where that "user_id" field is coming from .. any ideas ?

PS:

table engine_account is basically the Account class in the application named Engine