While I'm very disappointed that EUnet feels this way, I frankly don't
buy it at all.
Mnemonic support can be registered with IANA after the MIME document.
Nothing at all is lost. But meanwhile, we can't publish MIME, according
to the IESG, without deleting the MNEMONIC references.
If it comes down to choosing between IETF approval and EUnet approval, I
vote for IETF all the way. That leaves EUnet with the choice of either
registering their own extension to MIME in the approved way, which would
make a lot of sense, or else of designing their own alternative to MIME.
I think the latter would be rather foolish, but those are, to my mind,
the choices open to them. -- Nathaniel