Estimados,
Hace tiempo que tengo dudas con respecto a que si Exim esta realmente consultando los registros SPF al momento de recibir correos; y revisando un correo SPAM recibido el dia de hoy, me doy cuenta de que No esta verificando los SPF.
Acabo de recibir un correo cuyo supuesto dominio de origen es "tie.cl", al revisar los SPF para este dominio tenemos:
(SPF Query Tool)

SPF records are primarily published in DNS as TXT records.
The TXT records found for your domain are:
v=spf1 ip4:200.50.96.0/24 ip4:200.54.144.0/24 ip4:200.91.27.0/24 ~all<br>

SPF records should also be published in DNS as type SPF records.
No type SPF records found.

Checking to see if there is a valid SPF record.

Found v=spf1 record for tie.cl:
v=spf1 ip4:200.50.96.0/24 ip4:200.54.144.0/24 ip4:200.91.27.0/24 ~all

evaluating...
SPF record passed validation test with pySPF (Python SPF library)!
Sin embargo la IP de origen de este correo SPAM no estan dentro del rango de las IP's autorizadas para el dominio TIE.CL:

-------- Mensaje original --------
Return-path: <exhibits1201@tie.cl>
Envelope-to: micorreo@midominio.cl
Delivery-date: Thu, 12 Aug 2010 08:38:30 -0400
Received: from anupus.linksdelmundo.com ([190.196.7.226] helo=stealth2.santamail.info) by srv2.miservidor.cl with esmtps (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from <exhibits1201@tie.cl>) id 1OjX3G-0001jW-LM for micorreo@midominio.cl; Thu, 12 Aug 2010 08:38:30 -0400
Received: from [190.196.160.4] (helo=tie.cl) by stealth2.santamail.info with esmtpa (Exim 4.69) (envelope-from <exhibits1201@tie.cl>) id 1OjX0z-0001Ko-Kk; Thu, 12 Aug 2010 08:36:09 -0400
Message-ID: <fec4c98e1b26bfb5cebe6d02001aade0@tie.cl>
From: Exhibits <exhibits1201@tie.cl>
To: exh093@tie.cl <exhibits1201@tie.cl>
Subject: re: CHILEPLAST Plataforma de Negocios
Date: Thu, 12 Aug 2010 08:32:54 -0400
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="----=SPLITOR00A_001_35607296D"
X-AntiAbuse: This header was added to track abuse, please include it with any abuse report
X-AntiAbuse: Primary Hostname - stealth2.santamail.info
X-AntiAbuse: Original Domain - midominio.cl
X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse: Sender Address Domain - tie.cl
X-Spam-Status: No, score=1.1
X-Spam-Score: 11
X-Spam-Bar: +
En el WHM esta marcada la opcion que dice: "
Blacklist: SPF Checking"

Alguna sugerencia?