New proposal about forwarding

Hi,

I received a comment from a reader of my draft
which sounds interestingly, therefore I'd like
to forward it to you even if I have not yet
checked the RFCs 821 and 2821:

The proposal is to replace the envelope sender
address when forwarding into

[email protected]:[email protected]

which (allegedly) conforms to RFC 821, and
RFC 2821 still requires all MTAs to support it.

For bounces etc. MTAs are required by RFC 2821
to always send bounces to the rightmost address
([email protected])

In contrast, RMX would have to check the left
address (forwarder.example.org). 


I'm still not sure whether this has any advantage over
EHLO check, but I think it is worth to be taken into 
consideration (but I doubt that all MTAs support this). 

regards
Hadmut