Comparing non-English strings for sorting

["spamfilteraccount@gmail.com" <spamfilteraccount@gmail.com>]

Hi,

I see Emacs doesn't have builtin support for sorting non-Engish (UTF,
Unicode) strings in proper order.

Has anyone written a comparison function which can handle sorting such
strings if the character order is provided?

For example, in my case I'd supply the Hungarian alphabetical order as
a string ("aábcdeéfghijklmnoóöőpqrstuúüűxyvz") and the string
comparison function would use the character positions in this string
when comparing two strings do determine which is the lesser.

It couldn't handle all kinds of Unicode strings, of course, but it
would be an adequately simple solution for most of the Western
languages.

Someone may have already written this for some package, only I don't
know where to look. Any pointers?