[Greylist-users] Using a spam-trap e-mail address with greylist

[Frank Bax]

At 05:05 PM 1/25/07, Dennis Wynne wrote:
>Say I make up a new, bogus user for our domain and post it on various web
>pages, online sites, newsgroups, etc but never use it for mail. Then I would
>automatically black list any IP that sends an e-mail to that user since it
>has to be from a spammer.


OpenBSD calls this "Greytrapping"; included since 3.7 (May 2005).

http://www.openbsd.org/cgi-bin/man.cgi?query=spamd&sektion=8
http://www.openbsd.org/cgi-bin/man.cgi?query=spamdb&sektion=8

When a host that is currently greylisted attempts to send mail to a 
spamtrap address, it is blacklisted for 24 hours