First off let me say that when it works, it works beautifully. Calls, meeting invites, everything is great when configured correctly.
Im not sure if its a bug with this version or not (iPad version of Jabber works just fine) but every once in a while when launching the app, I get logged out of my phone services and cant log back in until I go and re-enter my server info and credentials. Its a weird bug that only seems to occur on iPhone deployments. Havent seen it happen on my iPad using the exact same information.
Dikbigerstaf about Cisco Jabber