I found this article about someone having the same problem trying to use Chinese characters. It seems the fix is in choosing the correct UTF setting in the database. Not sure it is exactly what you are looking for, but it may point you in the right direction: http://boringest.blogasian.com/2008/10/25/how-to-show-chinese-characters-in-wordpress/
hey hmansfield , thank you a lot for your tries . he's problem is that the database didn't accepte the chinese characters .. but my problem is database accepte arabic characters totally and works fine just a function break the slugs its something related with octets or something like that but i can not know wich function do that ; if i remove the sanitize_title_with_dashes works fine ! but it doesn't replace spaces with dashes .
In the article it looks like the author used a UTF setting that accepted both western and Chinese characters "utf8_unicode_ci". Wouldn't doing something like that allow you to use both sets of characters, keeping your permalink settings and URL structure as well? What do you think?
the problem isn't from database encodage , because when i use ugly title it accepte and all works fine , just when i use ugly slug before inserting it to the db a function break it ! i think the function is utf8_uri_encode() but im not sure i still analyse it .. thanks ..
solved: the problem is from the the post_name filed (varchar 200) ; big thanks to you hmansfield ; believe me i don't know how to give thanks to you . i'll be glad to be your friend and do anything to you if i can . // if you have msn PM me please with it .