Mail Delivery Failure - Headers

[apolix]

Someone sent an email to an invalid address on one of my servers and Exim produced one of its trusty "Mail delivery failed: returning message to sender" messages.

However the delivery report got rejected by the receiving MTA.

Since the receiving MTA belongs to one of my suppliers I decided to ask them what the problem was. They informed me that they were using the "Received:" header to validate against Joe-Jobs and my header was invalid:

Received: from mailnull by blaa.domain.com with local (Exim 4.63)
        id 1HdiSe-0005i2-Uj
        for user@blaa.com; Tue, 17 Apr 2007 09:50:48 +0200

They then started quoting RFC's to me telling me that "mailnull" was invalid since it did not contain any dots in it. And how they were using Exim too and what did I break to get it to show that....

Now I'm no expert on the SMTP RFC's but I have noticed that most cPanel servers produce headers like this when they produce delivery failure reports.

What is my solution - can I hack Exim to produce better headers? Or is this other mail admin not interpretting the RFC's correctly?

[nisse]

This is the default behaviour for Exim for locally-received messages; instead of showing the host, it shows the local user the message originates from. Exim runs as the user mailnull.

You can change the headers by adding the default headers to exim.conf and editing them:

received_header_text = Received: \
${if def:sender_rcvhost {from $sender_rcvhost\n\t}\
{${if def:sender_ident {from $sender_ident }}\
${if def:sender_helo_name {(helo=$sender_helo_name)\n\t}}}}\
by $primary_hostname \
${if def:received_protocol {with $received_protocol}} \
${if def:tls_cipher {($tls_cipher)\n\t}}\
(Exim $version_number)\n\t\
id $message_id\
${if def:received_for {\n\tfor $received_for}}