Please take a look at http://bugzilla.xfree86.org/show_bug.cgi?id=544 and http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=296719. Since there are a lot of free almost-full supported ISO10646 fonts in Linux, like unifont, xfonts-efont-unicode and xfonts-wqy. (You may find them in Debian) So I think that all of XLC_LOCALE for UTF-8 should be prior to use ISO-10646 earlier than ISO8859-1. Please consider to recover it. Thanks.
AFAIK, at least ja_JP.UTF-8 and zh_TW.UTF-8 are broken.
Sorry about the phenomenal bug spam, guys. Adding xorg-team@ to the QA contact so bugs don't get lost in future.
Downstream closed this as fixed, so I'm assuming it is fixed here. Please reopen if this is still an issue.
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