http://bugs.winehq.org/show_bug.cgi?id=30347
--- Comment #3 from Austin English austinenglish@gmail.com 2012-04-03 18:09:59 CDT --- Probably en_US.UTF-8. No, wine takes it from your environment (use locale or echo $LANG).
I've seen a similar issue where a game wouldn't install, because the locale was C/POSIX, which doesn't support that character.
Is there a download of this around?