When I extend the Django User using a OneToOneField to create a Manager, the  form to create a Manager in Django Admin only has fields for username and password.
class Manager(models.Model):
    """
    Users who need to login to manage the listing of a Outlet
    are represented by this model.
    """
    manager = models.OneToOneField(User)
    internal_notes = models.TextField(blank=True)
    def __unicode__(self):
        return self.manager.username
What is the right way to add the other built-in User fields like first_name etc to my Manager model?