i'm following the wiki at this location
Improving Anti-spam system - ZimbraWiki
to improve spam filtering. do i need to install postgrey? i'm using centos so i didn't know if i had to or not. i've done everything above in the tutorial.
i'm having a little trouble understanding the local.cf file additions/changes after PYZOR + RAZOR + SPF install like with the ratings but everything else has been done.