From LQWiki
Adding RBLs to your mail program
sendmail
In your sendmail.mc:
FEATURE(`dnsbl', `bl.spamcop.net', `"Spam blocked see: http://spamcop.net/bl.shtml?"$&{client_addr}')dnl
See RBL
In your sendmail.mc:
FEATURE(`dnsbl', `bl.spamcop.net', `"Spam blocked see: http://spamcop.net/bl.shtml?"$&{client_addr}')dnl
See RBL