On Sun, Mar 06, 2005 at 03:50:23AM -0500, Bob wrote: > Check the MX for the domain in dns to see if the mta now > connected is an authorized mta for the From: domain. If not,
Unfortunately this useful sounding check doesn't work. Many ISPs and many big users have different incoming and outgoing MTAs, and obviously only the incoming ones are listed as MXs, yet your connection will come from their outgoing MTA. For instance, my ISP's outgoing SMTP smarthost (which I don't use anyway, before anyone goes looking at my headers :-)) is 217.8.240.35, which is not one of my MXs (195.173.23.50 and 217.8.240.60). This sort of thing makes it much easier for them to have different rules and restrictions on outgoing mail than on incoming. Nick -- http://www.leverton.org/ ... So express yourself
