How to Reproduce

While doing a POST operation on /, Trac issued an internal error.

''(please provide additional details here)''

Request parameters:

{'__FORM_TOKEN': u'f9587050d5c2f937d5ee9335',
 'recaptcha_challenge_field': u'03AHJ_VustwH35-a2NICdiiAkabrReUL8PGRaBEdGwZgiiK9h1fdzyyi9qd1nDKs2v30v_6nv6c3HNI4F7Ky3yy30909rr_ctyIsIjM7hidvXWU1P-UKpMa0PmbogmaCjw-6XnMpyjXstMrCK9sKlmA7LLfZckAGfadQ',
 'recaptcha_response_field': u'edertso married'}

User agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:9.0.1) Gecko/20100101 Firefox/9.0.1

System Information

''System information not available''

Enabled Plugins

''Plugin information not available''

Python Traceback

Traceback (most recent call last):
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/main.py", line 511, in _dispatch_request
    dispatcher.dispatch(req)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/main.py", line 202, in dispatch
    chosen_handler)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/web/main.py", line 344, in _pre_process_request
    chosen_handler = filter_.pre_process_request(req, chosen_handler)
  File "/usr/local/lib/python2.6/dist-packages/TracSpamFilter-0.4.1dev_r10170-py2.6.egg/tracspamfilter/captcha/api.py", line 119, in pre_process_request
    del req.session['captcha_redirect']
KeyError: 'captcha_redirect'