utf-translate-cjk only settable via Customize

[Kai Großjohann]

Should a function for setting the variable be created?

My suggestion would be to create a function utf-translate-cjk-mode
based on the :set expression for utf-translate-cjk and then change
the :set expression to invoke that function.

OK to fix?

(There is a relation to the custom-setq discussion currently going
on -- when custom-setq is added to Emacs, the previously described
change might not be necessary anymore.)
-- 
A preposition is not a good thing to end a sentence with.