postmaster account problems

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Hi,

We are using Domino 5.11 on our V4R5 AS/400.

We are using the MTA.

Our AS/400 name is 'as400' and domain is 'domain.com.au'

When an external user sends an email to our domain but the address isn't
in the address book, the return mail isn't being sent to the user.

I have 'postmaster' set up as an alias on my Domino Account.

When I send an email to a nonexistent user I get a Delivery Failure 501
5.1.8 message.

When I look at the queue of our outgoing mail it says it is sending it
from 'postmaster@awh.com.au' but it never gets to the destination. And as
I have a 'postmaster' alias in my account I get the returned email.

The returned email says:

501 5.1.8 <postmaster@AS400.DOMAIN.COM.AU>... Domain of sender address
postmaster@AS400.DOMAIN.COM.AU does not exist

I don't think this is Domino related but AS/400 SMTP related.

What postmaster account does it use?  If I remove postmaster from my
account I never see these emails.

Is it a WRKDIRE issue? If so, what should I change or add?

Regards,

Nathan Simpson
Australian Wool Handlers
Forest Rd
Lara VIC  3212
(03) 5272 9227
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