Gajim is great. But it does not cover business use very well (until now). Think about preconfiguring deployed clients or not showing scary warnings about messages beying encrypted and RECORDED (meaning both participants can look at a history, later).
There once was spark <a href="http://www.igniterealtime.org/projects/spark/index.jsp" rel="nofollow">http://www.igniterealtime.org/projects/spark/index.jsp</a> but there seems to be no activity since 2011.<p>The author also mentions web clients: does anyone have found a usable one?