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Alternatively, a more complex scheme is to integrate it using Amavis, as described in IntegratedInPostfixWithAmavis.

Integrated into Qmail

SpamAssassin can be integrated into qmail system-wide using qmail-scanner, described in IntegratedInQmailWithQmailScanner.

Since qmail allows users to configure their own delivery options via ~/.qmail files, an alternative option, if you have spamd running and only want to scan mail delivered to local users, is to use ifspamh: see IntegratedInQmailWithIfspamh.

Can be integrated via qmail-scanner, an add-on to qmail. Info available at http://qmail-scanner.sourceforge.net/

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