X-Source headers does not work.

[anton_latvia]

hi,
I have "Track the origin of messages sent though the mail server by adding the X-Source headers (exim 4.34+ required)" checked, but nothing like this appears in outgoing mail. Is there any reason - why? I really need this one, because someone is using my server to send spam as nobody... X-SOURCE line does not appear in outgoing mail. We have:
WHM 10.8.0 cPanel 10.8.1-R113
CentOS 4.2 x86_64 - WHM X v3.1.0

And here is headers of outgoing spam...

1F4zTp-00075J-C3-H
nobody 99 500
<nobody@ns5.base-network.net>
1138967517 0
-ident nobody
-received_protocol local
-body_linecount 58
-auth_id nobody
-auth_sender nobody@ns5.base-network.net
-allow_unqualified_recipient
-allow_unqualified_sender
-local
XX
1
bruno1angel@yahoo.com.br

153P Received: from nobody by ns5.base-network.net with local (Exim 4.52)
id 1F4zTp-00075J-C3
for bruno1angel@yahoo.com.br; Fri, 03 Feb 2006 12:51:57 +0100
029T To: bruno1angel@yahoo.com.br
032 Subject: Alguem Lembrou de Voce
047F From: Humortadela <mensageiro@humortadela.com>
018 MIME-Version: 1.0
044 Content-type: text/html; charset=iso-8859-1
032 Content-Transfer-encoding: 8bit
051R Reply-To: Humortadela <mensageiro@humortadela.com>
040* Return-Path: mensageiro@humortadela.com
063I Message-ID: <a34a7811d4be2351261570075f7ddb63@humortadela.com>
014 X-Priority: 1
024 X-MSmail-Priority: High
052 X-Mailer: Microsoft Office Outlook, Build 11.0.5510
057 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1441
038 Date: Fri, 03 Feb 2006 12:51:57 +0100


Thanks in advance.

[anton_latvia]

By they way - the only way to get X-SOURCE header lines is to get a return mail - in returning Undelivered mail you can see those X-Source arguments. But why I can't see them in the mail queue?