cannot start a transaction within a transaction

[me@…]

Can't open Custom Query for the Roundcube Project.

Python traceback

Traceback (most recent call last):
  File "/usr/lib/python2.3/site-packages/trac/web/cgi_frontend.py", line 130, in run
    dispatch_request(req.path_info, req, env)
  File "/usr/lib/python2.3/site-packages/trac/web/main.py", line 139, in dispatch_request
    dispatcher.dispatch(req)
  File "/usr/lib/python2.3/site-packages/trac/web/main.py", line 116, in dispatch
    req.session.save()
  File "/usr/lib/python2.3/site-packages/trac/web/session.py", line 165, in save
    "AND var_name=%s", (v, self.sid, authenticated,
  File "/usr/lib/python2.3/site-packages/sqlite/main.py", line 237, in execute
    self.con._begin()
  File "/usr/lib/python2.3/site-packages/sqlite/main.py", line 503, in _begin
    self.db.execute("BEGIN")
DatabaseError: cannot start a transaction within a transaction

[sid]

What is the custom query you tried to run?

[cboos]

Probably an issue with the old (1.0.0 ?) PySqlite bindings. Never seen that with more recent releases.