greg
> I ... set up exactly the same system from the latest backup. All parameters, addresses are the same.
> However, the XP clients will not join the new domain on the new machine, despite it's identical to the old one.
Is it really identical ?
How did you perform the backup & restore ? Was it a full system backup and restore ? Did you use tape backup or something else ?
If correctly done, then all machine & user accounts & passwords should have been replicated and your workstations should have been able to login to the domain without problem. In that case report it as a bug against the backup method you used.
If you backed up/restored some other way, then you probably did not restore the complete amount of configuration data required eg machine accounts, secrets.tdb, which will prevent your existing workstations from logging in to the domain.