problem with RX subjects

[D Ivago]

Hello,

I'm running RH EL4 with SA 3.1.4 and postfix/procmail.

Last week I moved that mailserver to a datacenter and I'm  not sure if it's related, but since then I get more spam then ever. The server is now connected with 1 NIC on a 192.168.*.* subnet and routed via a h/w firewall to the internet, but I don't think SA cares about the local IP's anyway?

Alot of spam still gets properly filtered by SA but some spam manages to get in the inboxes. Mostely messages containing a subject wich starts like Re:RX.... and other subjects containint capital RX

What is the best way to block these kind of spams? My score is 3,0 atm but these spammails hardly get a core higher then 1

I have pasted some more detailed info below from the headers (my IP's and adressess are scrambled for privacy purposes).

Thanks for all suggestions!

Ivago

Header info
+++++++++++++++++++++++++++++++++++++++++++++
Return-Path: <[EMAIL PROTECTED] >
X-Spam-Checker-Version: SpamAssassin 3.1.4 (2006-07-25) on SOKAHO2.removed.be
X-Spam-Level:
X-Spam-Status: No, score=0.1 required=3.0 tests=BAYES_50,FORGED_RCVD_HELO,
     HTML_MESSAGE autolearn=ham version=3.1.4
X-Original-To: [EMAIL PROTECTED]
Delivered-To: [EMAIL PROTECTED]
Received: from kcg-inc.com ( ALagny-152-1-35-110.w83-112.abo.wanadoo.fr [83.112.228.110 ])
     by mail.removed.be (Postfix) with SMTP id D55B4103FDC
     for < [EMAIL PROTECTED]>; Sun, 27 Aug 2006 21:57:30 +0200 (CEST)
Received: by 192.168.xxx.64 with SMTP id QTRtOfzW;
     for <[EMAIL PROTECTED]>; Sun, 27 Aug 2006 12:59:10 -0700
Message-ID: <[EMAIL PROTECTED]>
Reply-To: "Hagen Mckechnie" <[EMAIL PROTECTED]>
From: "Hagen Mckechnie" < [EMAIL PROTECTED]>
To: [EMAIL PROTECTED]
Subject: Re: RXnyhe
Date: Sun, 27 Aug 2006 12:59:10 -0700
MIME-Version: 1.0
Content-Type: multipart/alternative;
     boundary="----=_NextPart_000_0001_01C6C9D8.96D1AB40"
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2800.1106
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106
Status: RO
X-UID: 12839
Content-Length: 2363
X-Keywords: