Spam proxy

 

A program that listens on two ports (POP3 and SMTP protocol). On POP3, it examines the downloaded messages to see if they are spam and takes action based on the result of the identification (mark the message, send a false "user does not exist" warning, etc...). On SMTP it just forwards the messages to some SMTP parent and stores the email addresses of the people I send the email to in a whitelist. The program is available with source code under GNU GPL license. It can be compiled under any kind of Unix, or in Windows using cygwin.