from the DiRT help file (the 3rd bullet is the guy you want):
"For systems installed with Exchange, these are tested scenarios:
- Restore a Unity backup to a server with a different name. All references to the old server name will be replaced in the database and registry such that this will go smoothly
- Restore a Unity backup to a server in a different domain. All references that include the old domain path will be fixed up during the restore.
- Restore a Unity backup on a system configured with a different back end connection so long as it?s Exchange based. Specifically you can backup a system running with Exchange 5.5 on box and restore the backup information onto a clean install of the same version of Unity that?s connected to Exchange 2000/2003 server off box. Any combination of 55/2K/2K3 and on/off box should work fine. The disaster recovery tools will make the changes in the database and registry to make this transition work. You cannot, however, migrate between Exchange back ends and Domino back ends or vice versa.
- Restore a Unity backup on a system that has Unity installed on a different drive and/or folder name. If the system you backed up was installed to c:\CommServer and the new system you restore to is installed on E:\Unity, the restore process will fix up all references necessary to make this work. "