Posting confirmation system

This system is wonderful. Where can I get more info about installing something like this on my mail server? thanks, Anthony ---------- Forwarded message ---------- Date: 8 Jan 2003 18:40:10 -0000 From: PHP Automoderator <confirm@php.net> To: art@sigiltechnologies.com Subject: PHP posting confirmation for art@sigiltechnologies.com This is an automatic reply to an email you sent to a PHP project mailing address protected by our 'self-moderation' system. To reduce the amount of spam received at these addresses, we require you to confirm that you're a real person before your email will be allowed through. All you have to do in order to have your original message sent is send an email to confirm@php.net with the following text (square brackets and all): [confirm: ba9167db0dfbb4a950f8b70e1cbb686c art@sigiltechnologies.com] which you should be able to do simply by replying to this email. (Don't worry, any leading text added for quoting will simply be ignored.) After we have received your confirmation, "art@sigiltechnologies.com" will be added to the list of pre-approved mail addresses for all of the PHP project mail addresses, your original message will be delivered, and future emails from that address will be delivered without delay automatically. You will not receive any confirmation of your confirmation -- your original message (and any other messages you have sent since then) will simply be sent to its original destination (possibly after a short delay). Sorry for the hassle, but the volume of unsolicited commercial email sent to these addresses has made this step necessary.