Scoring for Bayes

[Mark Nienberg]

I change the low probability Bayes scores so that when Bayes is
tricked, it doesn't subtract from the score.  I also change the scores
for Habeus and BSP for the same reason.  Anything that gives a negative
score is an attractive target for spammers.  They constantly work on
ways to trigger those negatives.  It has gotten so bad that Habeas is
actually a good indication of spam, when it was meant to be the
opposite.

Note that without bayes reducing scores for ham, you may have to bump
up your spam score a bit.  I'm using 5.5, and find that a few mailing
lists tend to generate false positives.

# habeas is often misused, don't allow a -8 reduction
score   HABEAS_SWE              -0.1

# Bonded Sender Program is sometimes misused, don't allow -4.3
score   RCVD_IN_BSP_TRUSTED     -0.1

# I'm not going to let Bayes reduce scores anymore
score BAYES_00 0 0 -0.05 -0.05
score BAYES_01 0 0 -0.04 -0.04
score BAYES_10 0 0 -0.03 -0.03
score BAYES_20 0 0 -0.02 -0.02
score BAYES_30 0 0 -0.01 -0.01

Mark