Email alias/forwarding to extrnl address

We have a large group of individuals that are part of our organization and need to recieve email via our domain name but then have it forwarded to their home email addresses so that they don’t need to use Outlook or OWA. With our current hosting provider I can setup an alias user id that forwards @ourcompany.com emails to their personal accounts. How can this be done on Exchange 2000? So far, I can either set them up to recieve an email via our domain OR I can have them setup as an external contact but I can get emails sent from outside to forward to their home addresses. Any ideas?