How can I set up support for sendmails anti-spam features?
This answer covers versions of sendmail from 8.9.3-20 (the version installed in Red Hat 6.2) upwards. If you have an older version, upgrade to sendmail 8.9. Stock sendmails can now do anti-spam exclusions based on a database of filter rules. The human-readable form of the database is at /etc/mail/access. The database itself is at /etc/mail/access.db. The table itself uses email addresses, domain names, and network numbers as keys.
