I successfully installed spamassassin & razor to run system wide on my
Debian Woody server.
apt-get installed spamassassin razor and libmilter-dev,
downloaded spamass-milter-0.1.2.tar.gz from http://www.milter.org, ungzipped
and untarred the file into /etc/mail,
followed the directions in /etc/mail/spamass-milter-0.1.2/README to compile
the milter, install the rc scripts, and edit and update sendmail.mc
changed /etc/default/spamassassin to set spamassassin to daemon mode.
verified that spamassassin was running by tailing /var/log/mail.log