The dovecot integration does not provide a server_password_change.d script: http://docs.univention.de/developer-reference-4.0.html#join:secret Therefore the configfiles using /etc/machine.secret will become invalid after some days.
Commit 61413 adds a server_password_change.d script.
OK: The script works as expected.
<http://errata.univention.de/ucs/4.0/237.html>