If you have experienced problem with our Jabber server, they should be fixed now.
The background is that we installed a new SSL certificate on 20 February 2021, but we missed attaching our signature correctly. Today, 26 February 2021, we fixed this problem.
Depending on your platform and settings, your XMPP (Jabber) client might have warned you about problems during this period.
There are no signs of attack attempts. This was simply a miss in our routines, for which we apologise.
Thank you for alerting us about this!