Although I am unaware of a method by which you can do this centrally from within Exchange, you could use the
Reply-To header to suggest alternate delivery of a reply message.
To do so, you would setup a "noreplies" mailbox and grant the "Send As" permission to those users who need such an ability. Then, in Outlook, select the "noreplies" mailbox as the "From" address, and specify the "Have replies sent to" option with the address of the actual user.
The "From" address line is hidden by default, you can enable it in the ribbon. The "Have replies sent to" option is under message options in 2003 and shows up in the ribbon as "Direct replies to" in 2007 and above.
Alternatively, if you require a non-interactive route, you could write a mail transport agent to check the contents of the
From header, and place the value of the
Return-Path header, which contains the actual user who sent the message, in the
If you really feel adventurous, you could write a transport agent which adds a
X-Noreplies-MessageID: SomeUniqueID header, record the original sender and the unique ID in a database, and perform the opposite operation on receipt of a message directed to noreplies.