Fixed the problem. Backed up the bayes tables with sa-learn --backup, and save the userpref and awl tables with mysqldump. Then deleted out the entire database, set everything to utf8 in my.cnf, recreated the database and tables using utf8 as the default character set. Then restored from backup with sa-learn --restore and created the awl and userpref tables with the mysqldump files (after editing them to use utf8 as the default character set).
Just in cases anyone else has this problem in the future...
