I was opened this idea 7 months ago:
http://wordpress.org/extend/ideas/topic/non-latin-characters-need-love
Still i couldnt find a solution for it.
Simply what i want?
Want to use “ÅŠİı ÄÄ Ãü Ãö çÔ turkish characters in permalinks / slugs.
You must go about the language functions-interface. See my example for german users: http://wordpress-buch.bueltge.de/wp-content/uploads/2010/05/de_DE.phps
We must also build differences on the permalinks for aour charachters in our language