How do I whitelist mail from internal processes?

[Alex Pimperton]

Hi All

I run MailScanner on a Debian box that also has LogWatch installed, and
recently emails from LogWatch are being tagged as High Scoring Spam
because the LogWatch report contains IP addresses that trip the SUBRL
rules in SpamAssassin.

I went to whitelist 127.0.0.1/my external IP but after checking the
headers I realised there's no IP address I can whitelist as the headers
are misssing the "Received: from" part.

My headers look like:

Delivered-To: root at erus.co.uk
Received: by mail.erus.co.uk (Postfix, from userid 0)
    id CB681581D5; Sun,  5 Feb 2006 00:31:25 +0000 (GMT)
To: root at erus.co.uk

How can I whitelist email that comes from internal processes
(LogWatch,Cron etc) without having to whitelist all email that arrives
for root?

Regards,

Alex

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