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chose an email account on the server to act as the model for SpamAssassin training. Using IMAP, create a SPAM and a HAM folder for this account. Copy messages that are spam into the SPAM folder and likewise for HAM. Run the following commands on the command-line, substituting the domain and user names where appropriate:

sa-learn –spam /var/qmail/mailnames/domain/user/Maildir/.SPAM/*

sa-learn –ham /var/qmail/mailnames/domain/user/Maildir/.HAM/*

After sufficient training, you’ll need to copy the resulting bayes_* files into each email account directory on the server (if you want to use this model’s training data server-wide, of course). Consider using the following one-liner to do this:

find /var/qmail/mailnames -type d -mindepth 2 -maxdepth 2 -exec cp -f /var/qmail/mailnames/domain/user/.spamassassin/bayes_* {}/.spamassassin/ \;

The above assumes a .spamassassin directory for each user

Edit
/etc/xinetd.d/smtp_psa

Add “-Rt0″ to “server_args”.
It will then look like this:

server_args = -Rt0 /var/qmail/bin/relaylock /var/qmail/bin/qmail-smtpd /var/qmail/bin/smtp_auth /var/qmail/bin/true /var/qmail/bin/cmd5checkpw /var/qmail/bin/true

Save the file, and restart xinetd:
/etc/init.d/xinetd restart