Is there a regfile anywhere that I can use to set up a new user's mailbox
automatically.

We run exchange 2003 and office 2003.

Basically the whole desktop setup is automatic, except for this part. I have
to log in as them, open outlook and tell it servername and username. Seems
like such a small step, there's got to be a way to automate it with
%username% and an entry for servername...