Sorting with international characters

[Arthur Clemens]

I am sorry if this has been covered before, but I cannot find an 
exclusive answer in the archives, and neither in the manual:

How to sort international characters?
I have managed to use store Unicode characters and to retrieve them 
again, but I see that sorting of Unicode chars is currently not 
supported.
So my questions:
1) Do I have to convert Unicode characters to the MacRoman character 
set? How about characters that are not in this set?
2) If not: how else to convert from and to Unicode, AND to sort?

System: Mac OS X - I have no experience with Mac OS 9.

Arthur Clemens