NDR Copy to Postmaster Account not working in Exchange 2007

Following Instructions from the following technet article  http://technet.microsoft.com/en-us/library/bb400930.aspx , I did the following

setup a mailbox for postmaster@domain.com.
Ran "set-organizationconfig -microsoftexchangerecipientreplyrecipient postmaster"
Ran "set-transportserver servername -externalpostmasteraddress postmaster@domain.com"

The postmaster mailbox is not receiving the copy of the NDR's...only the sender is .

We have a single Exchange 2007 SP1 server running on Windows Server 2008 that is internet facing.  We also have GFI Mail Essentials 14 running on the server.  I'm thinking that GFI is not recognizing the "Microsoft Exchange Recipient Primary SMTP Address" and is blocking these emails with Directory Harvesting.  

I've also tested setting up a transport rule where if user A sends an email to user B, then a bounceback message should be returned to user A.  These bounceback messages also are being blocked by directory harvesting.

Does anyone have a solution for this so that I can still use GFI Mail Essentials, but let my NDR copies and transport rule bounceback messages get through.  

I tested by sending a mesage from my mail account to a non-existent internal address. I recieved the bounce at my own email, but no copy arrives in the postmaster mailbox.