Is it possible to set Jive Messenger to only allow one concurrent session per username?
Not as far as I can tell but if such a feature were to exist I could see it being listed under server->resource policy.
Can be configured on the server side. My problem was that it also looks at the Resource type. I happened to be using two different clients, and they were defaulted to different resource types.
Well, a user with the same user name can still log on. They just need different resources, I guess i just misinterperted your question