This shows a real spam collected in a user quarantine. This shows the headers of the messages with the X-MailCleaner anti spam tags and filtering process

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for <john.doe@example.net>; Tue, 17 Jun 2014 12:38:19 +0200
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for users@spamassassin.apache.org; Tue, 17 Jun 2014 12:37:44 +0200
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for <users@spamassassin.apache.org>; Tue, 17 Jun 2014 12:37:44 +0200
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for <users@spamassassin.apache.org>; Tue, 17 Jun 2014 12:37:44 +0200
X-Injected-Via-Gmane: http://gmane.org/
To: users@spamassassin.apache.org
From: Walter Hurry <walterhurry@gmail.com>
Subject: No DNS available
Date: Tue, 17 Jun 2014 10:37:32 +0000 (UTC)
Lines: 9
Message-ID: <lnp5pc$du6$1@ger.gmane.org>
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I'm getting this:

eval failed: available_nameservers: No DNS servers available!

I do have nameservers available, and Net::DNS is installed, so I'm a bit
stuck.

Any advice?
Thanks