Blocking Email from Specific Addresses
We have created an easy and straight forward way to block email to a Virtual Server from a specific email address or domain name.
This feature allows you to specify individual mail addresses or whole hostnames that you do not want mail from. If someone is sending you and your users mail you can reject all email from that someone. You can also block all mail from any user by just specifying the hostname. (For more information about spam see Paul Vixie's page "Promote Responsible Internet Commerce: Fight SPAM").
Each Virtual Server has a ~/etc/spammers file which contains something like the following.
Lines that begin with "#" are comments. Other lines contain email addresses
or domain names that are blocked. If the Virtual Server is configured
as above, all email with email@example.com or cyberpromo.com in the "From:"
line of the header is blocked.
Many lists of reputed spammers have been compiled and made publicly available. You may or may not find these helpful.
Blacklist of Internet Advertisers
WebEasy - SPAM Database
Here are some other helpful URLS dealing with spam.