RE: comments on draft-ietf-impp-cpim-pidf-05

On 27 August 2002 20:30, Peterson, Jon wrote:
> > At the
> > moment, I can't really think of a suitable example where the
> > mustUnderstand attribute seems really useful, however. 
> 
> I've had some trouble with that myself, actually.

I went back in the archives to see where this began:

http://www.imppwg.org/ml-archive/IMPP-WG/200108/msg00017.html
http://www.imppwg.org/ml-archive/IMPP-WG/200109/msg00003.html
http://www.imppwg.org/ml-archive/IMPP-WG/200109/msg00005.html

It doesn't seem like a specific case was held in mind. It was maybe a
nice to have? Indeed, Hiroyasu Sugano made a comment at the time that
'even though the user agent cannot understand the "required" extension,
it cannot respond with a rejection error across the CPIM gateway'.

Can anyone think of a suitable example? 

Adrian.