Spammer Scott Whittle has harvested not only email addresses from the NANOG list archives, but also Message-IDs, and is busily trying to abuse the hell out of them. I've seen 6 (edit: 11) (edit: 14) copies so far this morning, and no doubt more are on the way. He identifies himself thusly: IP Technology Labs Network Communications Simplified Scott Whittle | President | T: +1 301 570 6611 x601 | M/SMS: +1 301 339 3237 | E: scott@IpTechnologyLabs.com | W: http://iptechnologylabs.com Although the spam itself carries a return address of Return-Path: <scott.whittle@iptechlabs.com> So blocking on the latter should suffice, at least for this round. ---rsk p.s. Pro tip: proofread your spam content before sending: "I am looking contact your Product Manager/Sales Manager regarding possible distribution of our USA made and designed Plug-and-Play VPN products. We are the are a channel friendly company, can offer account protection, and ensure your margins."