OperationalError: database is locked

New submission from lorph <None>:

==== How to Reproduce ====
While doing a GET operation on `/login`, Trac issued an internal error.
==== System Information ====
|| '''Python''' || `2.5.2 (r252:60911, Jul 22 2009, 15:34:27) `[[br]]`[GCC 4.2.4 (Ubuntu 4.2.4-1ubuntu3)]`[[br]] ||
|| '''Subversion''' || `1.4.6` ||
|| '''SQLite''' || `3.4.2` ||
|| '''pysqlite''' || `2.3.2` ||
==== Python Traceback ====
{{{
Traceback (most recent call last):
  File "/srv/trac/.local/lib/python2.5/site-packages/trac/web/main.py", line 377, in dispatch_request
    dispatcher.dispatch(req)
  File "/srv/trac/.local/lib/python2.5/site-packages/trac/web/main.py", line 237, in dispatch
    resp = chosen_handler.process_request(req)
  File "/srv/trac/.local/lib/python2.5/site-packages/trac/web/auth.py", line 100, in process_request
    self._do_login(req)
  File "/srv/trac/.local/lib/python2.5/site-packages/trac/web/auth.py", line 136, in _do_login
    db.commit()
OperationalError: database is locked
}}}
    

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Type     : defect
Component: core
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3979