You've got a BADLY illegal example - the one using ISO 10646 UCS-2
in 'text/plain'. The new top-level type 'widetext' can contain
UCS-2 (or actually only UTF-16 at present) and is under registration
on the MIME and Charsets lists. Character sets (like UCS-2) that
are not stream encoded multibyte (like UTF-8) or single-byte or
that don't have US-ASCII as a proper subset are ILLEGAL subordinated
to the top level type 'text'.
Paul Hoffman (Director of the Internet Mail Consortium, vendors of
mail gateways and tools) is the author of the 'widetext' and 'UTF-16'
Internet-Drafts (whose purpose is to allow XML in fixed-width
UTF-16 to be sent as a MIME enclosure). I'll look up the
exact I-D names and mail them out later today.
PLEASE remove the UCS-2 example from any IPP document, for the
present ('widetext' isn't MIME legal yet, so you can't reference
it in an example).
- Ira McDonald