FWIW: I've been tempted to implement sort of a "reverse blacklisting". If an (MX|provider) trips a 4xx threshold, have the local MTA s/4/5/ on emails to the problem (MX|domain). If it trips a 5xx threshold, including "upgraded" 4xx responses, simply refuse delivery altogether at the local end. "You don't like our email? Fine. You won't see it." We've observed good success convincing people to switch away from overly-draconian email providers... so a "reverse blacklist" might not be as _Wolkenkuckucksheim_ as it seems. Or, then again, it might. ;-) Eddy -- Everquick Internet - http://www.everquick.net/ A division of Brotsman & Dreger, Inc. - http://www.brotsman.com/ Bandwidth, consulting, e-commerce, hosting, and network building Phone: +1 785 865 5885 Lawrence and [inter]national Phone: +1 316 794 8922 Wichita ________________________________________________________________________ DO NOT send mail to the following addresses: davidc@brics.com -*- jfconmaapaq@intc.net -*- sam@everquick.net Sending mail to spambait addresses is a great way to get blocked. Ditto for broken OOO autoresponders and foolish AV software backscatter.