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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20020724

Description of problem:
Currently, iso8859-15 and iso8859-1 differ in handling of <dead_diaeresis>
<space>: the former generates quotedbl, and the letter produces diaeresis. 
Since <dead_diaeresis> <dead_diaeresis> already generates diaeresis and there's
no other easy way to generate quotedbl, the choice of en_US.UTF8 and iso8859-15
of generating quotedbl for the <dead_diaeresis> <space> composition looks sane,
so I'd like it to make it to iso8859-1 too.

Also, the iso8859-1 and iso8859-15 differ from en_US.UTF8 in a few double-accent
and accent-space pairs in that there are duplicates, sometimes conflicting ones,
in the iso8859 files.

The patch I'm attaching here, that I'm submitting to XFree86 too, should fix
these problems.