pykolab.log is empty

Hi Everyone,

after an upgrade from Debian Stretch to Buster I've been troubleshooting 
issues with kolab_smtp_access_policy.py and when trying to find the logs 
for it, I noticed that my pykolab.log is empty. What's strange is that 
the timestamp / last modified time on the file changes from time to time 
but it stays empty.

Any idea what could be wrong with the kolab logging?

Thanks

Eric