AttributeError: Cannot find an implementation of the "IRejectHandler" interface named "CaptchaSystem". Please update the option spam-filter.reject_handler in trac.ini.

How to Reproduce

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

''(please provide additional details here)''

Request parameters:

{'__FORM_TOKEN': u'dc37ea006efffc399f8d5c6f',
 'field_component': u'ui.dialog',
 'field_description': u'Ui.dialog close API should allow close without triggering the  event.\\r\\n\\r\\nCase in consideration - http://jsfiddle.net/aravindbaskaran/MJbr9/1/\\r\\n\\r\\nAPI required to allow closing of dialog in a non-cancellable way when done programmatically.',
 'field_summary': u'Ui.dialog close API should have a force mode, non cancelable with events',
 'field_type': u'feature',
 'field_version': u'1.10.4',
 'submit': u'Create ticket'}

User agent: beforeClose

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 237, in dispatch
    resp = chosen_handler.process_request(req)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/ticket/web_ui.py", line 170, in process_request
    return self._process_newticket_request(req)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/ticket/web_ui.py", line 396, in _process_newticket_request
    valid = self._validate_ticket(req, ticket)
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/ticket/web_ui.py", line 1182, in _validate_ticket
    for field, message in manipulator.validate_ticket(req, ticket):
  File "/usr/local/lib/python2.6/dist-packages/TracSpamFilter-0.4.1dev_r10170-py2.6.egg/tracspamfilter/adapters.py", line 81, in validate_ticket
    FilterSystem(self.env).test(req, author, changes, ip)
  File "/usr/local/lib/python2.6/dist-packages/TracSpamFilter-0.4.1dev_r10170-py2.6.egg/tracspamfilter/api.py", line 180, in test
    self.reject_handler.reject_content(req, 'Submission rejected as '
  File "/usr/local/lib/python2.6/dist-packages/Trac-0.12.1-py2.6.egg/trac/config.py", line 647, in __get__
    self.section, self.name))
AttributeError: Cannot find an implementation of the "IRejectHandler" interface named "CaptchaSystem".  Please update the option spam-filter.reject_handler in trac.ini.