* Steven Bellovin: > Right; I was not seriously suggesting that the DNS was the right > spot for it. I am seriously suggesting that a redirect mechanism -- > perhaps the email equivalent of HTPP's 301/302 -- would be worth > considering. Then, of course, there's problem of upgrading the > $\aleph_0$ mail senders out there to comply...
There's already SMTP support for this, see RFC 5321, section 3.4. This has been carried over from RFC 821, which already contain the 251/551 response codes. However, this is still a public database for which you cannot charge access, so it's not the solution we're looking for.
