>>Check out the "sql" directory in the tarball.
> The readme says to install msql-mysql-module. When doing this from cpan
> or downloading the tarball and running perl Makefile.PL:
> Where is your MySQL installed? Please tell me the directory that
> contains the subdir 'include'. [/usr/local] /usr/sbin
> Cannot find one of include/mysql/mysql.h, include/mysql.h in /usr/sbin
> at lib/DBD/mysql/Install.pm line 165, line 3.
> Searched for mysql.h and none was found. I have mysql 4.1 installed and
> running and working.

The mysql module is installed by default when you install spamassassin.
Run a check on your perl modules and you will see it under
Mail::Spamassassin. If you run spamassassin --lint -D look for your Bayes
contact and see what if any errors you have. All you should need is the
Bayes connection and username and password in local.cf. Make sure you run
them as your spamassassin user. Have you created the database and tables
for Bayes in mysql and can you connect to them via the mysql CLI?