perl-Mail-SPF-Query -- Query Sender Policy Framework<hr>
<a href="http://search.cpan.org/dist/Mail-SPF-Query/">http://search.cpan.org/dist/Mail-SPF-Query/</a><hr>
The SPF protocol relies on sender domains to publish a DNS whitelist
of their designated outbound mailers.  Given an envelope sender,
Mail::SPF::Query determines the legitimacy of an SMTP client IP.
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