Theres two parts to this question.
The Disaster recovery issue is pretty straight forward. We recommend a complete tape backup of your Unity box, including the Exchange directory. You can do this on line if youre using an appropriate backup package. The one weve tested in house is Backup Exec which works pretty well. I dont recommend the built in one that comes with Exchange
its free, but it has a lot of short comings. This doesnt seem to me to be the place to be cutting corners.
Changing the organization name in Exchange is a different story. They do have a MoveServer tool to help with stuff like this but its got some problems, not the least of which is it doesnt handle custom objects and properties terribly well and has a tendency to do bad things at the wrong time. If Unity is installed on the server, the move server tool will fail. Most folks dont trust it in general regardless.
Youre only good option is to reinstall, as you noted. We dont have an Export/Import tool for all Unity objects at this point so the short story is you will have to rebuild it from the ground up. You can check out the call handler export/import tool on my web page which will get all your call handlers, greetings and the like for your audio text applications but it wont backup everything else. Be aware this is not supported by Active Voice at the moment so you have to use it at your own risk.
Jeff Lindborg
Unity Product Architect
Active Voice
jlindborg@activevoice.com
http://members.home.net/jlindborg