A: 

Google search for "Content-Disposition filename encoding" gives as first result this:

http://stackoverflow.com/questions/93551/how-to-encode-the-filename-parameter-of-content-disposition-header-in-http

The accepted answer seems to be the answer to your request.

manixrock  2010-10-04 15:16:14
I've seen that, but its not much help.
Michael Simpson  2010-10-04 16:05:23

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