about spamassassin and dcc (freebsd 4.9 stable)

Hi folks,

I've installed spamassassin and dcc from port.
well, in my local.cf I've added 'use_dcc 1', but I don't really undestand
'dcc_body_max' 'dcc_fuz1_max' and 'dcc_fuz2_max'. what's the best
configuration?

thanks for your help
Regards
Andrea