I am currently evaluating jive messenger with the asterisk plugin, but I noticed a couple of issues.
When someone picks up the phone, his status is set to ''away'', that works perfect. But when that person transfers the call to another collegue his status remains ''away'' untill the user logs out of his jabber account. This happens however only to Zap channels, SIP phones work perfectly.
Also when somebody is on the phone, logs out his jabber client and logs back in his status is availlable. However, he is still on the phone.
These two problems prevent the plugin from being usefull to us. We are very interested to integrate jabber in our asterisk based PBX.