Question !!! (Score 1)

I wrote a work to compare techniques and open source tools to fight spam, and dspam wins: http://web.onda.com.br/nadal/Trabalho_Jeronimo_Zuc co.pdf What do you think about combining other methods (like SPF, DK, Reverse DNS, etc) on network level, before the mail are arrived ? Thanks and congratulation for your jobs !! Jeronimo Zucco