Changes since 1.991
===================
1.994 Thu Feb 26 17:23:15 EST 2004
Bugfix for Net::CIDR::Lite --- we now recognize 1.2.3/0 syntax not just
1.2.3.4/0
1.993 added support for caller-id
1.992 minor bugfixes. added fallback and override logic.
The SPF (Sender Permitted From) 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.