Answer one is the long way of performing this step, you do not need a separate profile.
In Outlook 2000 all you need to do is add the additional mailboxes to the Advanced tab of the Exchnage Service in your Outlook Profile, does require that you be using Corporate/Workgroup mode and not the IMO (Internet Mode). I currently have 8 account for which I am monitoring setup just as this.
When entering the name on the advanced tab, be sure to enter it exactly as shown in the display field. Otherwise Outlook may not be able to find the account.
To send a message as that account requries that you either have send as permission or be the owner / admin of the account. If you are neither you will not be permitted to send a message as this account.
Keep this in mind that when you send a message as another account your 'sent message' copy is found in your Sent Items folder and not the folder of the account you are sending as.
Good luck
-Rick