AttributeError: 'ModeratorNofityEmail' object has no attribute 'prev_cc'

[mehow]

How to Reproduce

While doing a POST operation on /ticket/2236, Trac issued an internal error.

All I tried to do is add myself to the cc list of a ticket. Taking into account I'm a new user, I assume Trac was trying to notify the moderator.

Request parameters:

{'__FORM_TOKEN': u'1949bde2ee6ff28a275e89a9',
 'action': u'leave',
 'cc_update': u'on',
 'comment': u'',
 'field_component': u'libtransmission',
 'field_keywords': u'IPv6',
 'field_milestone': u'None Set',
 'field_priority': u'Normal',
 'field_severity': u'Normal',
 'field_summary': u'transmission-remote over IPv6',
 'field_type': u'Enhancement',
 'field_version': u'1.71',
 'id': u'2236',
 'replyto': u'',
 'sfp_email': u'',
 'sfph_mail': u'',
 'start_time': u'1446044483621642',
 'submit': u'Submit changes',
 'view_time': u'1446044483621642'}

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.111 Safari/537.36

System Information

System information not available

Enabled Plugins

Plugin information not available

Python Traceback

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/Trac-1.0.6post2-py2.7.egg/trac/web/main.py", line 534, in _dispatch_request
    dispatcher.dispatch(req)
  File "/usr/local/lib/python2.7/dist-packages/Trac-1.0.6post2-py2.7.egg/trac/web/main.py", line 227, in dispatch
    resp = chosen_handler.process_request(req)
  File "/usr/local/lib/python2.7/dist-packages/Trac-1.0.6post2-py2.7.egg/trac/ticket/web_ui.py", line 182, in process_request
    return self._process_ticket_request(req)
  File "/usr/local/lib/python2.7/dist-packages/Trac-1.0.6post2-py2.7.egg/trac/ticket/web_ui.py", line 615, in _process_ticket_request
    valid = self._validate_ticket(req, ticket, not valid) and valid
  File "/usr/local/lib/python2.7/dist-packages/Trac-1.0.6post2-py2.7.egg/trac/ticket/web_ui.py", line 1300, in _validate_ticket
    for field, message in manipulator.validate_ticket(req, ticket):
  File "/usr/local/lib/python2.7/dist-packages/TracTicketModerator-0.7_devel-py2.7.egg/ticketmoderator/api.py", line 731, in validate_ticket
    tn.notify(req, ticket, id)
  File "/usr/local/lib/python2.7/dist-packages/TracTicketModerator-0.7_devel-py2.7.egg/ticketmoderator/notification.py", line 117, in notify
    self.prev_cc += old and self.parse_cc(old) or []
AttributeError: 'ModeratorNofityEmail' object has no attribute 'prev_cc'