At first, since Exchange 2000 you need a 1:1 relation between an user account and a mailbox. Now user can have more then one mailbox and now mailbox can have more then one owner.
You can do this:
– All off your users need an own mailbox and mail address
– create a “dummy” user for the shared mailbox and mail address
– open the mailbox with outlook and share the inbox (and all needed folders) to the other users with level 8
– Edit the security settings of the dummy user in AD and add the users to the ACL. Add the rights “send as” and “receive as”.
– Add the inbox and all needed folders from “dummys” mailbox to the outlook profile of your users.
– Add the field “From” to the outlook new mail window
All users should have access to the folders of the “dummy” user, now. And all users should have the right to send mail with this one mail address if they select it for the “From” field.
To share send mails you can create a outlook rule what moves the mails from the personal outbox of each user to the outbox of the shared mailbox.
Alternative you can use a mail enabled public folder for this task. But I’m not sure if “send as” is possible for a public folder in exchange 2003.