http://www.postfix.org/postconf.5.html#postscreen_dnsbl_reply_map
shouldn't here be a placeholder for the IP available the first version below works fine in case of responsible admins since the text is contained in bounces i would like to give them a clickable link which already contains the IP address zen.spamhaus.org zen.spamhaus.org; http://www.blacklistalert.org/ zen.spamhaus.org zen.spamhaus.org; http://www.blacklistalert.org/?q=<client-ip>