On Thu, Jun 29, 2006 at 04:54:54PM +0100, Nigel Metheringham wrote: > How many MTAs accept a 551 redirect when they are sending mail on to
> another MTA?
None that I know of, but I plan to send a patch for Exim if the developers are
interested.
Note that, as per RFC 2821, you can't assume any particular behaviour from the
sender. If you use this code, you accept the responsability that mail could be
bounced instead of redirected.
Needless to say, I expect this to change with time ;).
> Of those that don't, what happens? Dropped mail, bounced?
Any sane MTA would bounce it, like with the other 5xx codes.
