We are configuring SpamAssassin. Here's what we found to help out.
The Apache SpamAssassin Project http://spamassassin.apache.org/
The SpamAssassin Wiki: http://wiki.apache.org/spamassassin/FrontPage
The SpamAssassin Configuration Generator (2.5.x) http://www.yrex.com/spam/spamconfig.php
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