[FATAL] Shutting down because of exception: exceptions.NameError

[Squirrel Remailer Admin <admin@squirrel.theremailer.net>]

I keep getting these exceptions in my log (0.0.5.1, Python 2.2.3+):

Sep 25 18:52:54.745 [FATAL] Exception while running server
Sep 25 18:52:54.764 [FATAL] Traceback (most recent call last):
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/ServerMain.py", line 1095, in runServer
    server.run()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/ServerMain.py", line 821, in run
    self.mmtpServer.process(2)
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 100, in process
    self.readers[fd].handleRead()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 483, in handleRead
    self.__handleAll()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 501, in __handleAll
    self.__state()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 443, in __readFn
    self.finished()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 1011, in __receivedAck
    self.beginNextMessage()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 935, in beginNextMessage
    self._getNextMessage()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 965, in _getNextMessage
    self._curMessage = m.getContents()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/MMTPServer.py", line 777, in getContents
    return self.pending.getMessage().getPacket()
    File "/home/miniond/lib/python2.2/site-packages/mixminion/server/ServerQueue.py", line 179, in getMessage
    self.message = self.queue.store.getObject(self.handle)
    File "/home/miniond/lib/python2.2/site-packages/mixminion/Filestore.py", line 320, in getObject
    except cpickle.UnpicklingError, e:
  NameError: global name 'cpickle' is not defined
Sep 25 18:52:54.765 [FATAL] Shutting down because of exception: exceptions.NameError