I have this entry in my ~/.mailcap file:

application/vnd.ms-powerpoint; /cygdrive/c/Program\ Files/Microsoft\ Office/Office12/POWERPNT.EXE "`cygpath --windows %s`"

`mailcap-parse-mailcaps' parses it and makes an entry in
`mailcap-mime-data' as:

(("application"
  ("vnd\\.ms-powerpoint"
   (viewer . "/cygdrive/c/Program\\ Files/Microsoft\\ Office/Office12/POWERPNT.EXE \"`cygpath --windows %s`\"")
   (type . "application/vnd\\.ms-powerpoint"))
  ))

Note that the MIME type is regexp-quote'd.  Because of this POWERPNT
doesn't run automatically when playing such parts.  May I install
the patch attached below?  Otherwise is there any deep reason r-q
is indispensable?