AOL's MTAs silently drop mail instead of denying it at the border.

No, they don't: Return-Path: <> Delivered-To: shields@challah.msrl.com Received: (qmail 15733 invoked by alias); 21 Feb 2000 17:17:31 -0000 Delivered-To: alias-msrl-shields@msrl.com Received: (qmail 15730 invoked for bounce); 21 Feb 2000 17:17:30 -0000 Date: 21 Feb 2000 17:17:30 -0000 From: MAILER-DAEMON@challah.msrl.com To: shields@msrl.com Subject: failure notice Lines: 29 Xref: challah.msrl.com MSRL.COM:10378 Hi. This is the qmail-send program at challah.msrl.com. I'm afraid I wasn't able to deliver your message to the following addresses. This is a permanent error; I've given up. Sorry it didn't work out. <ntbhekcaedkreukdr@aol.com>: 205.188.156.130 does not like recipient. Remote host said: 550 MAILBOX NOT FOUND Giving up on 205.188.156.130. --- Below this line is a copy of the message. Return-Path: <shields@msrl.com> Received: (qmail 15728 invoked by uid 1000); 21 Feb 2000 17:17:10 -0000 Sender: shields@challah.msrl.com To: ntbhekcaedkreukdr@aol.com Subject: test From: Michael Shields <shields@msrl.com> Organization: Mad Science Research Labs Date: 21 Feb 2000 17:17:10 +0000 Message-ID: <87n1oueaqx.fsf@challah.msrl.com> Lines: 3 User-Agent: Gnus/5.0803 (Gnus v5.8.3) XEmacs/21.1 (Bryce Canyon) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii -- Shields. -- Shields.