Fixed the detection of when a custom manager is required because an 'objects'

from django.db.models.query import QuerySet

from django.dispatch import dispatcher

from django.db.models import signals

from django.db.models.fields import FieldDoesNotExist

from django.utils.datastructures import SortedDict

# Size of each "chunk" for get_iterator calls.

    cls = sender

    if not hasattr(cls, '_default_manager'):

        # Create the default manager, if needed.

        if hasattr(cls, 'objects'):

            raise ValueError, "Model %s must specify a custom Manager, because it has a field named 'objects'" % name

        try:

            cls._meta.get_field('objects')

            raise ValueError, "Model %s must specify a custom Manager, because it has a field named 'objects'" % cls.__name__

        except FieldDoesNotExist:

            pass

        cls.add_to_class('objects', Manager())

dispatcher.connect(ensure_default_manager, signal=signals.class_prepared)