Technically, you could use (fboundp 'char-to-unicode) or something
like that which is specific to the Unicode support which started in
21.5.8 or so. But your version test is a lot easier to understand.
The attached patch crudely fixes it. Unless someone objects or
up with a better way to fix it, will apply in a couple of days.
2007-05-08 Ville Skyttä <scop(a)xemacs.org>
* start-files/ja/locale-start.el (command-line-do-help):
Don't try to load `un-define' with XEmacs >= 21.5.
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