I don't know. Evaluating (set-coding-category-system 'utf-8 utf-8) produces:
Symbol's value as variable is void: utf-8
On 10/7/05, Stephen J. Turnbull <stephen(a)xemacs.org> wrote:
 >>>>> "Eduards" == Eduards Mihelovics <emikhelo(a)gmail.com>
writes:
 Eduards> When I run M-x prefer-coding-system utf-8, I get: Can't
 Eduards> prefer coding system utf-8.
 That's an XEmacs bug, I've confirmed it. Evaluating the expression
 (set-coding-category-system 'utf-8 utf-8)
 then doing prefer-coding-system should make it work. I don't know
 exactly what's gone wrong here. Ben? (The full thread is at
 
http://list-archive.xemacs.org/xemacs-beta/200510/msg00013.html )
 Eduards> (Same response with any other coding system)
 Eduards> Should it work in the latest beta?
 Any coding system except 'binary or 'iso-8859-1 (by design, since
 preferring them would completely prevent autodetection), or utf-8
 (because of the bug) should work. 'iso-2022-jp and 'iso-8859-15 work
 for me.
 --
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