Hi,

The following problem is happening with Exchange 2003 Server Enterprise SP1,
running on Windows Server 2003 Standard (no service pack).

I have two AD mailboxes set up: let's call them Account1 and Account2.  The
Account1 mailbox is forwarded to Account2, with the "deliver to both
mailboxes" option ticked.

The Account2 mailbox has some delivery restrictions set on it - mail from
internal senders is delivered without restriction, but external senders are
blocked, except for a small list of SMTP addresses, which have been set up as
AD contact objects.  There are no such restrictions on the Account1 mailbox.

Messages sent directly to Account2 behave as expected: Internal AD users are
fine, external addresses in the Allow list deliver OK as well, while other
external senders get an NDR.

However, when an external email is sent to Account1 and the address is not
in the allow list for Account2, no delivery takes place to _either_ mailbox,
and the external sender gets an NDR as follows:

------------------
This is an automatically generated Delivery Status Notification.

Delivery to the following recipients failed.

       Accou***@here.there.com


From: External Sender <Sen***@other.place.com>
To: Accou***@here.there.com
Subject: T E S T
Sent: Tuesday, 4 April 2006 1:57:37 PM
------------------

Note that, for the external sender, they don't know anything about
"Account2", as they originally sent to Account1.

Has anyone seen this before, or have any idea why this behaviour would occur?

I've checked everything I can think of, and searched all over the place. 
Any assistance would be appreciated!

Cheers,

-Ben.

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