I guess it says something about the varying different configurations and slight differences XMPP servers can have when even after several months of public testing there were still some serious bugs in the 2.1 release. I know there there are many people who are dependent on Monal for day to day use and I am fixing everything as quickly as I can. I will put out 2.1.2 soon with further connectivity fixes.
There are some problems connecting to Jabberd servers with 2.1. I have fixed that in 2.1.1, which should be available soon.
Going forward please file all new bugs at the new, more modern bug tracker:
You can get it here: