spam blocking

[niti]

hi all   i m running hp-ux 11.0 qmail server and the server performs very slow , probably 'coz of spam mails and increased queue size   I have tried testing and installing a lot many scripts and codes available on lwq and qmail.org but was not successful in any of them 'coz of some or the other issues. I have now latest qmail-ldap patch having the more of antispam techniques. but i need to trace the spammer everytime ... i have tried spamguard and spamcontrol but hp-ux creates issues.   i usually block spammer via my badmailfrom file in /var/qmail/control .Scanning scripts for subj and attachments needs to b set up for already traced spammer .(in .qmail file)this does not rectify my problem.can anybody sugg. me the solution .I require that my server shd automaticaly detect the spammer and block it in badmailfrom   and what more shd  i do to optimise the performance??? hlp soon   regards niti