IntegrityError: duplicate key violates unique constraint "session_pk"

[anonymous]

How to Reproduce

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

(please provide additional details here)

Request parameters:

{'group': u'status',
 'milestone': u'0.11',
 'status': [u'assigned', u'new', u'reopened']}

System Information

Trac	0.11dev-r6772
Python	2.4.3 (#2, Oct 6 2006, 07:49:22) [GCC 4.0.3 (Ubuntu 4.0.3-1ubuntu5)]
setuptools	0.6c7
psycopg2	2.0.5.1
Genshi	0.5dev-r816
Pygments	0.9
Subversion	1.3.2 (r19776)

Python Traceback

Traceback (most recent call last):
  File "/usr/local/virtualenv/lib/python2.4/site-packages/Trac-0.11dev_r6772-py2.4.egg/trac/web/main.py", line 417, in _dispatch_request
    dispatcher.dispatch(req)
  File "/usr/local/virtualenv/lib/python2.4/site-packages/Trac-0.11dev_r6772-py2.4.egg/trac/web/main.py", line 222, in dispatch
    req.session.save()
  File "/usr/local/virtualenv/lib/python2.4/site-packages/Trac-0.11dev_r6772-py2.4.egg/trac/web/session.py", line 84, in save
    (self.sid, self.last_visit, authenticated))
  File "/usr/local/virtualenv/lib/python2.4/site-packages/Trac-0.11dev_r6772-py2.4.egg/trac/db/util.py", line 50, in execute
    return self.cursor.execute(sql_escape_percent(sql), args)
  File "/usr/local/virtualenv/lib/python2.4/site-packages/Trac-0.11dev_r6772-py2.4.egg/trac/db/util.py", line 50, in execute
    return self.cursor.execute(sql_escape_percent(sql), args)
IntegrityError: duplicate key violates unique constraint "session_pk"