smf-grey (Sendmail GreyList milter)

smf-grey is a lightweight, fast and reliable Sendmail milter that implements the Greylisting anti spam technology as proposed by Evan Harris. This technology can significantly reduce the amount of spam and worms going from zombie hosts, which may produce up to 80% of world SPAM. This milter has a very effective Greylisting algorithm on the base of this tuple: sender's IP address (Class C subnet), envelope sender address and envelope recipient address. It's a lite alternative for the milter-greylist, graymilter and milter-gris milters. It's written in C.

  · external editable configuration file;
  · whitelist by an IP address (in CIDR notation);
  · whitelist by a PTR (reverse DNS) record;
  · whitelist by an envelope sender e-Mail address;
  · whitelist by an envelope recipient e-Mail address;
  · whitelists auto reloading;
  · scalable and tunable fast in-memory greylist/autowhitelist engine;
  · autowhitelisted records reloading and regular dumping;
  · SMTP AUTH support;
  · RFC-2821 standard compliance;
  · Greylisting results header builder.

smf-grey v2.1.0 (Feb 1 2007)
milter-spamblocker v3.5 (Sender/Recipient Address Verification + smart GreyListing)

:: Add-ons ::
  extended version of smf-grey by Tim Kleingeld (Australia)

:: Testimonials ::
  Appie Verschoor (Netherlands)
      "I would like to thank you for the simple and very effective program. It actually blocks 90% of spam attempts before they even hit my mailserver."

  William Montgomery (United States of America)
      "We have used your milter for a few months now and are very impressed with its performance. This has reduced our spam load by a huge amount - great work."