wiki moinmoin1.9.7 一個問題，用戶登陸後任何預覽都要出錯，不知何因。

wiki moinmoin1.9.7 一個問題，用戶登陸後任何預覽（即便不修改內容）都要出錯,以下：

The server encountered an internal error and was unable to complete your request.  Either the server is overloaded or there is an error in the application.

若是沒有用戶登陸，修改、預覽沒有任何問題。

試了WINDOWS , UBUNTU12.04做服務器，都同樣。 moinmoin 服務器端提示以下：

2014-01-01 16:14:11,673 INFO MoinMoin.web.serving:41 192.168.0.138 "GET /moin_static197/modern/img/moin-conflict.png HTTP/1.1" 200 -
2014-01-01 16:14:13,990 INFO MoinMoin.web.serving:41 192.168.0.138 "GET /DOS%E5%9C%A8%E8%BF%99%E9%87%8C HTTP/1.1" 200 -
2014-01-01 16:14:29,002 INFO MoinMoin.web.serving:41 192.168.0.138 "GET /DOS%E5%9C%A8%E8%BF%99%E9%87%8C?action=edit&editor=text HTTP/1.1" 200 -
2014-01-01 16:14:35,645 ERROR MoinMoin.wsgiapp:293 An exception has occurred [http://192.168.0.88:8080/DOS%E5%9C%A8%E8%BF%99%E9%87%8C].
Traceback (most recent call last):
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 282, in __call__
    response = run(context)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 88, in run
    response = dispatch(request, context, action_name)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 136, in dispatch
    response = handle_action(context, pagename, action_name)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 195, in handle_action
    handler(context.page.page_name, context)
  File "/home/samxiao/moin-1.9.7/MoinMoin/action/edit.py", line 152, in execute
    pg.sendEditor(preview=savetext, comment=comment)
  File "/home/samxiao/moin-1.9.7/MoinMoin/PageEditor.py", line 296, in sendEditor
    self._save_draft(raw_body, rev)
  File "/home/samxiao/moin-1.9.7/MoinMoin/PageEditor.py", line 856, in _save_draft
    cache_data = cache.content()
  File "/home/samxiao/moin-1.9.7/MoinMoin/caching.py", line 285, in content
    raise CacheError(str(err))
CacheError
2014-01-01 16:14:35,666 INFO MoinMoin.web.serving:41 192.168.0.138 "POST /DOS%E5%9C%A8%E8%BF%99%E9%87%8C HTTP/1.1" 500 -
2014-01-01 16:14:35,694 ERROR werkzeug:116 Error on request:
Traceback (most recent call last):
  File "/home/samxiao/moin-1.9.7/MoinMoin/support/werkzeug/serving.py", line 159, in run_wsgi
    execute(app)
  File "/home/samxiao/moin-1.9.7/MoinMoin/support/werkzeug/serving.py", line 146, in execute
    application_iter = app(environ, start_response)
  File "/home/samxiao/moin-1.9.7/MoinMoin/support/werkzeug/wsgi.py", line 411, in __call__
    return self.app(environ, start_response)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 282, in __call__
    response = run(context)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 88, in run
    response = dispatch(request, context, action_name)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 136, in dispatch
    response = handle_action(context, pagename, action_name)
  File "/home/samxiao/moin-1.9.7/MoinMoin/wsgiapp.py", line 195, in handle_action
    handler(context.page.page_name, context)
  File "/home/samxiao/moin-1.9.7/MoinMoin/action/edit.py", line 152, in execute
    pg.sendEditor(preview=savetext, comment=comment)
  File "/home/samxiao/moin-1.9.7/MoinMoin/PageEditor.py", line 296, in sendEditor
    self._save_draft(raw_body, rev)
  File "/home/samxiao/moin-1.9.7/MoinMoin/PageEditor.py", line 856, in _save_draft
    cache_data = cache.content()
  File "/home/samxiao/moin-1.9.7/MoinMoin/caching.py", line 285, in content
    raise CacheError(str(err))
CacheError

新註冊一個用戶，編緝同一個頁面，就沒問題。奇怪啊！