pykolab errors new users can't login

[Jan Kowalsky]

Hi all,

suddenly in a running kolab 3.4 installation we run into pykolab errors.

kolab 3.4 on debian wheezy
pykolab 0.7.10-0~kolab4

At the same time there are no mailboxes created for new users and they
can't login.

/var/log/pykolab.log (with debug level 9)

2017-05-09 17:45:25,175 sqlalchemy.engine.base.Engine INFO SELECT
entry.id AS entry_id, entry.uniqueid AS entry_uniqueid,
entry.result_attribute AS entry_result_attribute, entry.last_change AS
entry_last_change
FROM entry
WHERE entry.uniqueid = ?
 LIMIT ? OFFSET ?
2017-05-09 17:45:25,175 sqlalchemy.engine.base.Engine INFO
('2e1e2e81-e22711e5-b755f717-8e34c29f', 1, 0)
2017-05-09 17:45:25,175 sqlalchemy.engine.base.Engine INFO
('2e1e2e81-e22711e5-b755f717-8e34c29f', 1, 0)
2017-05-09 17:45:25,223 pykolab.imap DEBUG [23173]: Logging on to Cyrus
IMAP server localhost
2017-05-09 17:45:25,223 pykolab.auth ERROR An error occured using
_persistent_search: AttributeError("'int' object has no attribute 'split'",)
2017-05-09 17:45:25,223 pykolab.auth ERROR Exception occurred:
IOError(5, 'Input/output error')
2017-05-09 17:45:25,223 pykolab.daemon ERROR Error in process
'Kolab(example.org)', terminating:
	IOError(5, 'Input/output error')

Any ideas for further debugging?

thanks and best regards
Jan