$ telnet smtp.yourdomain.org 25 Connected to smtp.yourdomain.org. Escape character is '^]'. 220 smtp.yourdomain.org ESMTP spamd IP-based SPAM blocker; Thu Oct 9 16:52:31 2008 EHLO mydomain.org 250 Hello, spam sender. Pleased to be wasting your time. MAIL FROM: 250 You are about to try to deliver spam. Your time will be spent, for nothing. RCPT TO: 250 This is hurting you more than it is hurting me. data 451 Temporary failure, please try again later. Connection closed by foreign host.