sendmail invocation for "empty sender" bounces

[Bernhard Reiter]

On Wednesday 18 October 2006 20:37, Kjetil Torgrim Homme wrote:
> > Unfortunately, "<>" is not recognised as the "empty sender" by our
> > sendmail implementation. Instead, it expects "" (which looks a lot more
> > logical to me, too, given that < and > may not be part of an email
> > address which is what is expected to come after the -f).
>
> then it's not a Sendmail compatible interface, and you should report the
> bug to your MTA provider.  plenty of software will expect this to work.
> the <> are optional around an address.

AFAIR supporting the empty sender aka <> is mandatory for MTAs,
e.g. for sending bounces.
I do not have the RFCs at hand right now, so I cannot look for it. 
So sorry for the fuzzy pointer.