E-mails estranhos 1

Comunidade Free,
Boa noite!

EStou enfrentando um problema com um novo cliente meu que não esta fácil!! Tá entrando uns e-mails estranhos em algumas caixas postais. Eu estou achando que é alguém usando o servidor para enviar spam...mas não tenho certeza. Neste cliente ele usa servidor de e-mail postfix com SpamAssassin. Segue abaixo uma das mensagens.

OBS. aonde esta xxxxx@dominio.com.br - quero dizer ser umas das caixas postais que recebem estes tipos de e-mail.

Desde já agradeço ...

Abraço

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Hi. This is the qmail-send program at mx1.valuehost.ru.
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

<ya-telion@yandex.ru>:
77.88.32.35 failed after I sent the message.
Remote host said: 554 5.7.1 Content-Policy reject msg: Message rejected under suspicion of spam.; S8226459AbYAUSKq

--- Below this line is a copy of the message.

Return-Path: <rafaela@transcaxias.com.br>
Received: (qmail 73707 invoked by uid 89); 21 Jan 2008 21:10:09 +0300
Delivered-To: serg@telion.ru
Received: (qmail 67928 invoked by uid 89); 21 Jan 2008 21:08:59 +0300
Received: from 184-26-231-201.fibertel.com.ar (HELO pxcs) (201.231.26.184)
by mx1.valuehost.ru with SMTP; 21 Jan 2008 21:08:53 +0300
Received: from [201.231.26.184] by mail.transcaxias.com.br; Mon, 21 Jan 2008 15:05:02 -0300
Message-ID: <01c85c3e$ff67f570$b81ae7c9@rafaela>
From: =?koi8-r?B?Iu7Jy8/Mwcr3wcTCwczY08vJyiI=?= <rafaela@transcaxias.com.br>
To: <post@telion.ru>
Subject: * =?koi8-r?B?8sHT09nMy8kg0M8g18Hbxcog1MXNwdTJy8U=?=
Date: Mon, 21 Jan 2008 15:05:02 -0300
MIME-Version: 1.0
Content-Type: multipart/alternative;

boundary="----=_NextPart_000_0007_01C85C3E.FF67F570"
X-Priority: 3
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