I am using Miranda (0.8 Alpha #17) as my IM client and Openfire (3.5.2) as my XMPP server. I had a lot of problems with this configuration. Each time I connects, all seems to be correct (get my contact list, transports are starting...) but finally all stops without any error messages, and leaving me thinking I am connected.
After lot of search and multiple tests I finally find out where was the problem.
Miranda Stream compression is incompatible with OpenFire.
I don't know which one is wrong but since I disabled stream compression in Miranda my connection is working like a charm.