One distinction between most of these threads and this one was that I
propose that we use the mime nomenclature and semantics as directly as
possible (via the mime namespace) rather than mimicing them in xml via
things like xml:content-type and xml:packing.
The two mime names that are needed for inline binary entities are
"mime:Content-type" and "mime:Content-transfer-encoding". The latter can
only use the "base64" encoding for binary data as "7bit" and "8bit" clash
with XML.
If we can agree on a URI for the mime namespace, we could potentially start
merrily transferring binary content inline in our XML documents. OK, so I'm
a naive wild-eyed optimist :-).
~gabe