我已按照http://code.google.com/p/pubsubhubbub/wiki/DeveloperGettingStartedGuide中的说明设置集线器。当我启动集线器时，我收到以下警告
$ sudo python2.5 google_appengine/dev_appserver.py pubsubhubbub/hub/
INFO 2010-03-04 12:29:57,928 appengine_rpc.py:157] Server: appengine.google.com
INFO 2010-03-04 12:29:57,959 appcfg.py:329] Checking for updates to the SDK.
WARNING 2010-03-04 12:29:58,272 datastore_file_stub.py:418] Could not read datastore data from /tmp/dev_appserver.datastore
WARNING 2010-03-04 12:29:58,273 datastore_file_stub.py:418] Could not read datastore data from /tmp/dev_appserver.datastore.history
INFO 2010-03-04 12:29:58,349 dev_appserver_main.py:465] Running application pubsubhubbub on port 8080: http://localhost:8080
当我将浏览器指向时http://localhost:8080，我的浏览器和控制台中抛出了一个令人讨厌的异常。AttributeError
ERROR 2010-03-04 12:31:27,735 dev_appserver.py:3000] Exception encountered handling request
Traceback (most recent call last):
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 2969, in _HandleRequest
base_env_dict=env_dict)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 406, in Dispatch
base_env_dict=base_env_dict)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 2238, in Dispatch
self._module_dict)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 2156, in ExecuteCGI
reset_modules = exec_script(handler_path, cgi_path, hook)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 2052, in ExecuteOrImportScript
exec module_code in script_module.__dict__
File "/home/pentarim/webdev/pshb/pubsubhubbub/hub/main.py", line 116, in <module>
import dos
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1158, in Decorate
return func(self, *args, **kwargs)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1806, in load_module
return self.FindAndLoadModule(submodule, fullname, search_path)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1158, in Decorate
return func(self, *args, **kwargs)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1708, in FindAndLoadModule
description)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1158, in Decorate
return func(self, *args, **kwargs)
File "/home/pentarim/webdev/pshb/google_appengine/google/appengine/tools/dev_appserver.py", line 1659, in LoadModuleRestricted
description)
File "/home/pentarim/webdev/pshb/pubsubhubbub/hub/dos.py", line 219, in <module>
offset_multi=memcache.offset_multi,
AttributeError: 'module' object has no attribute 'offset_multi'
INFO 2010-03-04 12:31:27,749 dev_appserver.py:3029] "GET / HTTP/1.1" 500 -
作为一个python新手需要帮助，有什么想法吗？