Content-encoding and external message converters?

frystyk@w3.org (Henrik Frystyk Nielsen) said:
> The MIME parser stream takes out the metainformation and adds it to 
> the  anchor. When all the metainformation is parsed, thestream goes 
> into  transparent mode and lets the body pass untouched. 

This comment raises something that I don't understand with the stream
stack protocols.  There doesn't seem to be any means of handling
conversions that relate to encodings and other envelope information.
I'd like to expand the MIME parser to handle headers like

	Content-Transfer-Encoding: base64
	Content-Type: message/partial
	Content-Type: message/external-body

but I'm at a loss how to go about it with the stream plumbing that
now exists.

I'd also like to see support for the RFC1867 header line:
	Content-Disposition: form-data; name="xxx"; filename="yyy"
but that looks easy to do using HTMIME_register.
73 de ke9tv/2, Kevin KENNY   GE Corporate Research & Development
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