[Simple] MSRP-ACM compatibility

[Hisham Khartabil <hisham.khartabil at gmail.com>]

The MSRP-ACM draft has an open requirements question on backwards
compatibility with endpoints that use MSRP relays. In San Francisco
some 20 or so people raised their hands one way or another on this
question, yet only a much smaller number have engaged in the list
discussion.

Please offer your opinions on the following questions. We'd appreciate
the reasoning behind your opinions, rather than just yes or no votes.
We'd really like to hear from every person who raised a hand in San
Francisco. If you stated an opinion at the microphone, please restate
it here.

1) Is there a requirement for an endpoint that uses the C-line
addressing mechanism in the MSRP-ACM draft to be able to talk to an
endpoint that uses an MSRP relay (RFC 4976).

2) If you said yes to 1), is it acceptable to update RFC 4975 and/or
RFC 4976 to achieve compatibility?  If so, how extensively?

Much appreciated,
Hisham