SpamAssassin just became a lot better with Bayesian-style analysis.
Cool.
Justin Mason wrote:
OK folks -- SpamAssassin 2.50 is now up on /released/ . Please
download and install!
http://SpamAssassin.org/downloads.html
This should be considered a beta release.
Main changes since 2.4x:
- Bayesian filtering, using a Bayesian-style form of
probability-analysis classification. This uses an algorithm based on
the one detailed in Paul Graham's 'A Plan For Spam' paper, along with
aspects taken from Graham Robinson's work, and the chi-combining
technique developed by the SpamBayes project.
- Auto-learning. This trains the Bayesian filter automatically,
based on the results from traditional SpamAssassin diagnosis. It
uses a set of heuristics and separate thresholds to ensure (as much
as is possible) that it trains on guaranteed non-spam and spam.
Old, unused tokens are automatically expired.
- much-improved rule set. A whole new set of rules based on
Message-Id analysis is now in place, which accurately detects forged
headers from a wide range of spamware. Many inaccurate rules have
been dropped. HTML tests much improved, with a set to detect
image-only spam.
- new default format for detected-spam messages; the message is
encapsulated as a MIME part, with a preview and the spam report in
the main part of the message.
- Score sets. Based on whether you are using just SpamAssassin
rules, adding network tests, and using a trained Bayesian database,
SpamAssassin will use a set of scores appropriately to gain the
maximum degree of accuracy.
- Italian, Polish, Spanish, French and German rule sets and
translations.
- Much improved reliability with spamd. The problems with signals
have been cleared up thanks to a pipe-based child tracking system,
and all spamd-hanging bugs reported have proved unreproducable.
- Unicode problems with Red Hat 8 and perl 5.8 fixed. Works on Perl
5.005, 5.6.x, and 5.8.x.
- Taint-safe. SpamAssassin runs with perl's taint-checking enabled
for better security.
- Razor 1 support is now officially deprecated.
- "spamc -c" was not working, fixed. This fix required increasing
the revision of the spamd protocol; only difference is that now more
than one protocol header can appear in the reply from spamd.
- all fixes from 2.44 included.
--j.
