The anti-spam situation has changed too significantly since the days in which we did this research, and there are many, better sites to obtain this kind of instructional information. It is our opinion that our configurations should not, at the present point, be used due to the dated nature of the configurations we offered online.
Good and current resources on Procmail anti-spam recipes can be found from www.procmail.org.
Good and current resources on Sendmail can be found from www.sendmail.org.