[SunHELP] Mail bounce problem

[Matt Braun]

Hey all.

I'm having trouble with some, but not all, outbound and inbound
mail. When mail is sent to us from certain external sites (erols being one
of them), it bounces. When we try to send mail to them we get:

   ----- The following addresses had permanent fatal errors -----
<vahfma at external.com>

   ----- Transcript of session follows -----
... while talking to mx.mail.rcn.net.:
>>> RCPT To:<vahfma at remotesite.com>
<<< 550 cannot route to sender address <mjbraun at internal.com>
550 <vahfma at external.com>... User unknown

This is on a Solaris 8 box running Sendmail version 8.9.1

The mail server has a private ip address and is behind a firewall
(fire.internal.com). The firewall's IP is in the MX record for
"internal.com" but it forwards port 25 to
the actual server "triumph.internal.com". In the sendmail.cf for triumph,
masquerading is enabled as "DMinternal.com". Users are using Outlook to
send and receive mail internally, and it's the only mail server.


Note: I am not the designer or builder of this network; I just get to fix
it.

What could be going wrong here?

===========[b l i x]============
"Rub the bee. Rub the bee.
Keep rubbing the bee or damn
  your eyes, your life is ashes.
YOUR LIFE IS ASHES."
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