Having two separate Mailboxes in Outlook 2003

Hi Guys
I have come across a bit of an issue, I would like to have two mail boxes on a single Outlook 2003, however this can be done.But I’d want this set up is so that if the person viewing both mailboxes sends a mail from any mailbox, it send the mail with that sepcific mailboxes STMP mail address, and not the holders address.
Can this be done???