I'm running Exchange 2003 Enterprise Edition SP2 and I was wondering if it is possible to have it send an automated message to an external recipient who tried to send an e-mail to a member who has left our organization (e.g. user X, who is external to our organization, sends a message to user Y, who left our organization a week ago), something like 'The user you are trying to contact has left the organization, your mail will NOT be forwarded". Please note that the user who has left the organization has been disabled and his mailbox purged.
Is this possible within Exchange?
Thanks in advance.