On 2008-10-06 at 20:19 -0700, Claus Assmann wrote:
> Why not add support for PRDR? Take a look at the (unfortunately
> expired) internet draft from Eric A. Hall:
>
> SMTP Service Extension for Per-Recipient Data Responses (PRDR)
>
> It is supported by one MTA (MeTA1, see http://www.meta1.org/).
Reading the PRDR draft, it's almost identical in the protocol changes to
EXDATA, which is an older draft and implemented in Courier, we're told.
The real difference is that PRDR uses unwrapped response codes, so that
you get multiple top-level responses, in the style of LMTP, but without
claiming to be other than SMTP, which means that it's breaking the
protocol. Mind, that doesn't matter much since it has to be requested.
Since Tony is listed in the Acknowledgements for the PRDR draft, I'd be
interested in knowing his opinion.
-Phil
