How do I keep e-mail on the AS/400 for a user when all other e-mail is forwarded?

[Jim Langston <jlangston@xxxxxxxxxxx>]

I am trying to set up a routine/procedure where customers can e-mail EDI
files to us.  The theory is to e-mail these to the AS/400 where we can do
some magic (haven't even though about that part yet) and strip out the
attachment and receive the file into our EDI package.

The problem, however, is that we have the AS/400 set up to forward all
e-mail to our mail server.

So, when I try to send e-mail to our AS/400 for a user it gets sent to our
mail server which barfs on it.

I've tried sending it to: testing@cels400  which gets translated to
testing@cels400.celsinc.com, sent to our mail server which kicks me back an
undeliverable message.

In the SMTP attributes I see the mail router is set up as our e-mail server.

Is there anything I can do to receive an e-mail to a user called TESTING (or
whatever) and keep it on the AS/400 for processing, while keeping the rest
of the e-mail being sent to our mail server?  The reason we are directing
all mail to the mail server is because the AS/400 itself sends e-mail.

Any help or suggestions are appreciated.  This is a totally new project and
I am open for other/better ways to do this also.

Regards,

Jim Langston