[SC-Help] Spamcop treats MX differently depending on where it appears in chain

[You have no need to know]

I am seeing problem when my ISP's mail servers don't report the name that
Spamcom expects in their received line.

If the MX is the first receiver it gets marked as the spam source rather
than the original source. (Before someone asks, the ISP has two names and
all MXs for one are MXs for the other. I have munged one as ISP.MX and the
other as isp-other-name.mx)

e.g.
Received: from 4dmail.co.uk (p548FF904.dip.t-dialin.net [84.143.249.4])
	by OTHERNAME.FOR.ISP.MX (Postfix) with ESMTP id 60BB36E;
	Tue, 29 Mar 2005 05:56:46 +1000 (EST)

Received:  from OTHERNAME.FOR.ISP.MX (othername.for.isp.mx [1.2.3.4]) by isp-other-name.mx (Postfix) with ESMTP id 8E0685B588A; Tue, 29 Mar 2005 06:03:20 +1000 (EST)
....
1.2.3.4 is not an MX for othername.for.isp.mx
host othername.for.isp.mx (checking ip) ip not found ; othername.for.isp.mx discarded as fake.
cannot find an mx for othername.for.isp.mx
cannot find an mx for isp.mx
....
host OTHERNAME.FOR.ISP.MX (checking ip) ip not found ; OTHERNAME.FOR.ISP.MX discarded as fake.
   Chain test:OTHERNAME.FOR.ISP.MX =? 1.2.3.4
   1.2.3.4 is not an MX for OTHERNAME.FOR.ISP.MX
   host OTHERNAME.FOR.ISP.MX (checking ip) ip not found ; OTHERNAME.FOR.ISP.MX discarded as fake.
   cannot find an mx for OTHERNAME.FOR.ISP.MX
   cannot find an mx for isp.mx
   Chain test failed
....
1.2.3.4 not listed in dnsbl.sorbs.net


If the MX is NOT the first receiver it gets accepted as a relay after its
address is matched to one of the addresses in the MX records.

e.g.
Received: from smarthost3.tiscali.dk (smarthost3.tiscali.dk [62.79.79.29])
	by OTHERNAME.FOR.ISP.MX (Postfix) with ESMTP id
	9B56E1E for <x>; Wed, 30 Mar 2005 10:15:40 +1000 (EST)
Received: from cpmail.dk.tiscali.com (mail.tiscali.dk [212.54.64.159])
	by smarthost3.tiscali.dk (8.13.1/8.13.1) with ESMTP id j2U0Bpuw026791;
	Wed, 30 Mar 2005 02:12:05 +0200 (CEST)

Received:  from smarthost3.tiscali.dk (smarthost3.tiscali.dk [62.79.79.29]) by OTHERNAME.FOR.ISP.MX (Postfix) with ESMTP id 9B56E1E for <x>; Wed, 30 Mar 2005 10:15:40 +1000 (EST)
....
1.2.3.4 not listed in dnsbl.sorbs.net
   Chain test:OTHERNAME.FOR.ISP.MX =? othername.for.isp.mx
   host othername.for.isp.mx (checking ip) = 1.2.3.4
   1.2.3.4 is an MX for isp.mx
   1.2.3.4 is mx
   OTHERNAME.FOR.ISP.MX and othername.for.isp.mx have close IP addresses - chain verified

-- 
Avoid reality at all costs.
$email =~ s/n(.)a(.)n(.)a(.)e(.+)invalid/$1$2$3$4$5au/;
icbm: 33.43.46S 150.59.27E