I have some legitimate emails with score equal to 0 still marked as spam. After further checking, I found that it is marked as XBL+RBL but without score. Is spamassassin have mechanism to force an email as Spam without any score.
No, SpamAssassin does not have such an option.. well, except the -t command line parameter which forces it to spam-tag everything regardless of score. (-t is test mode)
Are you by any chance using MailScanner?? It will force the spam tag, regardless of SA score, if one of it's RBLs matches.. adust your MailScanner.conf to disable "spam lists".
