IIRC, I had set years ago the spam threshold to 6 and the ham to 0 or something. In the db configuration settings added were two new ones, BayesAutoLearnThresholdSpam and BayesAutoLearnThresholdNonSpam. Which is somewhat strange, since things did work before even though these were set.
Digging around I saw that if these two are not configured, then scores of 6 and -1.15 for spam and ham are set in /etc/mail/spamassassin/local.cf. Which also seems ok...
Still not sure if bayesian training is in place or not. Bayes definitely does not work, since I do not observe the usual BAYES_xx SA tags in my emails (see previous message).
I'm adding my own /etc/mail/spamassassin/local.cf file here:
#------------------------------------------------------------
# !!DO NOT MODIFY THIS FILE!!
#
# Manual changes will be lost when this file is regenerated.
#
# Please read the developer's guide, which is available
# at http://www.contribs.org/development/
#
# Copyright (C) 1999-2006 Mitel Networks Corporation
#------------------------------------------------------------
# bayes_learn_to_journal 1
dns_available yes
internal_networks x.y.z.w
lock_method flock
loadplugin Mail::SpamAssassin::Plugin::TextCat
ok_languages en el
ok_locales en el gr
bayes_path /var/spool/spamd/.spamassassin/bayes
bayes_file_mode 750
report_safe 0
required_score 6
rewrite_header Subject [SPAM]
skip_rbl_checks 0
clear_trusted_networks
trusted_networks x.y.z.w 127/8 x.y/16
use_bayes 1
bayes_auto_learn 1
bayes_auto_learn_threshold_nonspam -1.15
bayes_auto_learn_threshold_spam 6
add_header all Status _YESNO_, score=_SCORE_ required=_REQD_ autolearn=_AUTOLEARN_
add_header all Details _REPORT_