使用Django的manage.py命令运行Celery时,它返回一个奇怪的错误

% python manage.py celeryd -l INFO                                                                                                     ~/Workspace/django-projects/project/src
Traceback (most recent call last):
  File "manage.py",line 11,in <module>
    execute_manager(settings)
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/django/core/management/__init__.py",line 438,in execute_manager
    utility.execute()
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/django/core/management/__init__.py",line 379,in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/django/core/management/__init__.py",line 261,in fetch_command
    klass = load_command_class(app_name,subcommand)
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/django/core/management/__init__.py",line 67,in load_command_class
    module = import_module('%s.management.commands.%s' % (app_name,name))
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/django/utils/importlib.py",line 35,in import_module
    __import__(name)
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/djcelery/management/commands/celeryd.py",line 13,in <module>
    class Command(CeleryCommand):
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/djcelery/management/commands/celeryd.py",line 17,in Command
    option_list = CeleryCommand.option_list + worker.get_options()
  File "/home/damon/Workspace/django-projects/project/env/lib/python2.6/site-packages/celery/bin/celeryd.py",line 89,in get_options
    conf = self.app.conf
AttributeError: 'NoneType' object has no attribute 'conf'

这是版本信息：

% python                                                                                                                               ~/Workspace/django-projects/project/src
Python 2.6.5 (r265:79063,Apr 16 2010,13:57:41) 
[GCC 4.4.3] on linux2
Type "help","copyright","credits" or "license" for more information.
>>> import celery
>>> print celery.VERSION
(2,2,'a1')
>>> import djcelery
>>> print djcelery.VERSION
(2,'a1')