Somebody on the NANOG mailing list has their mail pointing to tcwireless.us, which is throwing challenge/response mail like the following: Your message From: Valdis.Kletnieks@vt.edu To: n3td3v <xploitable@gmail.com> Subject: Re: Fwd: cnn.com - Homeland Security seeks cyber counterattack system ( Einstein 3.0) Date: 10/6/2008 has been just received by gmail.com mailserver. To prove that your message was sent by a human and not a computer, please visit the URL below and type in the alphanumeric text you will see in the image. You will be asked to do this only once for this recipient. http://mail.tcwireless.us/challenge/?folder=2008100614384085099427 Your message will be automatically deleted in a few days if you do not confirm this request. ===================================================== DO NOT REPLY TO THIS MESSAGE. NO ONE WILL RECEIVE IT. ===================================================== Note it says 'gmail.com mailserver'. Paul Ferguson reported to me that the one he saw said 'received by vt.edu mailserver'. Also note that the From/To has lost nanog@nanog.org - for both my note and Paul's (in fact, looking at Paul's actual posting and mine show nanog@nanog.org as being the only common link, thus the "must be a nanog subscriber" conclusion). Please, if you're going to use a C/R, at least learn how to whitelist the mailing lists you're on. And if you can't figure out how to do that, please do us all a favor and not try to run an operational network...