Postfix: gate local users

[Mark Gillingham <markgill@uwalumni.com>]

As usual, I'm confused. My users get mail via a Netware system, but a 
Debian box often must send mail to them. How do I tell Postfix to gate 
all local mail to the Netware systems. The format is as follows:

username@localhost   -->  username@mydomain.org

Thanks.

Mark