Django MOD_PYTHON错误

问：

我已经让 django 与 mod_python 一起运行了一段时间，但今天我收到以下错误

MOD_PYTHON ERROR

ProcessId:      4551
Interpreter:    'thatch'

ServerName:     'thatch'
DocumentRoot:   '/var/www/thatch'

URI:            '/'
Location:       '/'
Directory:      None
Filename:       '/var/www/thatch/'
PathInfo:       ''

Phase:          'PythonHandler'
Handler:        'django.core.handlers.modpython'

Traceback (most recent call last):

  File "/usr/lib/python2.5/site-packages/mod_python/importer.py", line 1537, in HandlerDispatch
    default=default_handler, arg=req, silent=hlist.silent)

  File "/usr/lib/python2.5/site-packages/mod_python/importer.py", line 1202, in _process_target
    module = import_module(module_name, path=path)

  File "/usr/lib/python2.5/site-packages/mod_python/importer.py", line 304, in import_module
    return __import__(module_name, {}, {}, ['*'])

ImportError: No module named django.core.handlers.modpython

这是我的虚拟主机配置

<VirtualHost *:80>
  ServerName  thatch

  DocumentRoot /var/www/thatch

  <Location "/">
    SetHandler python-program
    PythonPath "['/var/www/thatch'] + sys.path"
    PythonHandler django.core.handlers.modpython
    SetEnv DJANGO_SETTINGS_MODULE thatch.settings
    PythonOption django.root /var/www/thatch
    PythonDebug On
  </Location>

  <Location "/media">
    SetHandler None
  </Location>

  <LocationMatch "\.(jpg|gif|png|css|js)$">
    SetHandler None
  </LocationMatch>

</VirtualHost>

知道为什么会发生这种情况吗？