BlackMail 0.31

BlackMail is a highly configurable SMTP mail filter that runs at a system level as a proxy to your existing mailer. Selectively reject bogus or spam mail during receipt, saving you extra storage space or irate users.
Blackmail operates at a system-wide level: all incoming and optionally outgoing mail is filtered.Will block unwanted mail relaying (if your mailer is unable to) and spams.
The filtering consists of various checks on the SMTP envelope and message headers: if any tests fail then the mail will be bounced. Blackmail can...
Check against spam sites
Check against spam keywords
Check host names and email addresses using DNS for validity
Check against the RBL (Realtime Blackhole List) for spam IP addresses
Check that To: and From: address do not match (a common spam signature)
Check correct header formation e.g. Message-ID
The spam sites and spam keywords are of your choice, you can block who or what you want. Minimal sample lists are provided.
BlackMail is known to work with:
Mailers: Smail, Sendmail, Qmail, Fetchmail
OSes: Aix, various BSD, Irix, Linux, NeXTStep 3.x, Solaris, SunOs, SVR4 (Re-confirmation is required for some of these OSes.)
It should be possible to use BlackMail with most SMTP mailers on most UNIX systems. Blackmail is not designed to run on Windows or OS/2, but if you wish to port it...
Enhancements:
- Removed old reference to www.bitgate.com