I just installed SpammAssasin 3.0.0, on RHES3, after fixing the LANG as it still seems to have problems with utf-8. Anyhow, after reading about the AutoWhitelist I looked and the directory /var/spool/spamassassin did not exist and I get autolearn=failed in my headers. Maybe something has to do with the other?
Do you have DB_File installed (provided you're not using the option to dump to SQL.)?