smf-grey is a Sendmail milter that implements the GreyList Anti SPAM technology.

This technology can significantly reduce the amount of SPAM and viruses going from zombie computers (infected Windows PC), which produce more than 80% of SPAM.

GreyList Sendmail milter has a very effective GreyList algorithm on the base of the tuple: sender IP address (C class subnet), sender envelope and recipient envelope.

It's very recommended to use the smf-grey milter combined with the smf-zombie and the smf-spf milters. It's a triple impact on SPAM and viruses, that will seriously increase the efficiency of filtration.

This milter aims to be lightweight, reliable and simple. It's written in C.

Here are some key features of "GreyList Sendmail milter":
· It has a hosts/networks whitelist;
· It has an autowhitelist;
· It can add the information header with GreyList results to scanned messages;
· It can log all milter activities through the syslog service.

Advantages:

· Small code;
· Fast work;
· Stability (production quality);
· Few system resources are required.

What's New in This Release:
· Whitelists auto reloading was implemented.
· Autowhitelisted records regular dumping and reloading was implemented.
· The default greylisting time period was increased.
· New TODO tasks were added.
· Cosmetic enhancements were made.