[Samba] Painless migration from 2.2.x on old server to 3.0.x on new server needed ASAP

[Chris]

I need to painlessly migrate on old Samba 2.2.x installation to a new 
server running 3.0.x (3.0.14a for now).

Time is of the essence as a hardware problem is causing intermittent 
operation of the old server that seems to be getting worse (actually it 
is looking doubtful that it will be back up at this point).

I do have a backup of the smb.conf, the Samba .tdb 
files, /etc/passwd, /etc/shadow.

The old server was a PDC implementation so it is very important that the 
users maintain their same profiles (they are local, but there's about 
150 users spread around 10 machines).

So how to implement this on the new server?
Also is it mandatory that the new server need to have the same DNS name?

Any help. clues, experience in this would be greatly appreciated.

Thank you.

Chris