If you would like copies of “NDR” messages to go to the postmaster, you can simply set this up in Exchange. To do this:
* Exchange 5.5: Properties of Internet Mail Service, “Internet Mail” tab, click the “Notifications” button
* Exchange 2000: Properties of your Virtual Server, “Messages” tab, add an entry to “Send a copy of NDR’s to”
NOTE a) Not necessary to restart the service.
NOTE b) Its always best to ensure you’re running the latest Exchange Service Pack (at time of writing, the latest are Exchange 5.5 SP4 and Exchange 2000 SP3)