mailfilter to identify and mark spam
SpamAssassin is a mail filter to identify spam.

Using its rule base, it uses a wide range of heuristic tests on
mail headers and body text to identify "spam", also known as
unsolicited commercial email.

The spam-identification tactics used include: 

header analysis: 
                spammers use a number of tricks to mask their
                identities, fool you into thinking they've sent a
                valid mail, or fool you into thinking you must have
                subscribed at some stage.  SpamAssassin tries to
                spot these.

text analysis:
                again, spam mails often have a characteristic style
                (to put it politely), and some characteristic
                disclaimers and CYA text.  SpamAssassin can spot
                these, too.

blacklists: 
                SpamAssassin supports many useful existing blacklists,
                such as mail-abuse.org, ordb.org or others.

Razor:          
                Vipul's Razor is a collaborative spam-tracking
                database, which works by taking a signature of spam
                messages. Since spam typically operates by sending
                an identical message to hundreds of people, Razor
                short-circuits this by allowing the first person
                to receive a spam to add it to the database -- at
                which point everyone else will automatically block
                it.

Once identified, the mail can then be optionally tagged as spam for
later filtering using the user's own mail user-agent application.

SpamAssassin requires very little configuration; you do not need
to continually update it with details of your mail accounts, mailing
list memberships, etc.  It accomplishes filtering without this
knowledge, as much as possible.

Read /usr/local/share/doc/SpamAssassin/README
for further installation instructions.

Or if you are in a hurry you can read:
/usr/local/share/doc/SpamAssassin/OpenBSD-SpamAssassin-mini-howto.html

The SpamAssassin Wiki is available at <http://wiki.apache.org/spamassassin>
and contains up-to-date information on configuring SpamAssassin, and using
some of the more advanced features of it.

Maintainer: Marc Balmer <mbalmer@openbsd.org>

WWW: http://spamassassin.apache.org/
