TypeError: Error when calling the metaclass bases

[philipmutua]

I get a these logs below when I try to run:
python manage.py syncdb --settings=accounting.settings.local

TypeError: Error when calling the metaclass bases
    metaclass conflict: the metaclass of a derived class must be a (non-strict) subclass of the metaclasses of all its bases

logs in detail

Traceback (most recent call last):
  File "manage.py", line 10, in <module>
    execute_from_command_line(sys.argv)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 443, in execute_from_command_line
    utility.execute()
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 382, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 261, in fetch_command
    klass = load_command_class(app_name, subcommand)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 69, in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name, name))
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/south/management/commands/__init__.py", line 10, in <module>
    import django.template.loaders.app_directories
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/template/loaders/app_directories.py", line 21, in <module>
    mod = import_module(app)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/utils/importlib.py", line 35, in import_module
    __import__(name)
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/constance/__init__.py", line 3, in <module>
    config = Config()
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/constance/config.py", line 10, in __init__
    utils.import_module_attr(settings.BACKEND)())
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/constance/backends/database/__init__.py", line 22, in __init__
    from constance.backends.database.models import Constance
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/constance/backends/database/models.py", line 7, in <module>
    from picklefield import PickledObjectField
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/picklefield/__init__.py", line 5, in <module>
    from picklefield.fields import PickledObjectField # reexport
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/picklefield/fields.py", line 79, in <module>
    class PickledObjectField(_get_subfield_superclass()):
  File "/home/aphya1/projects/AcornAccounting/acornaccounting/local/lib/python2.7/site-packages/django/db/models/fields/subclassing.py", line 15, in __new__
    new_class = super(SubfieldBase, cls).__new__(cls, name, bases, attrs)
TypeError: Error when calling the metaclass bases
    metaclass conflict: the metaclass of a derived class must be a (non-strict) subclass of the metaclasses of all its bases