I am using Mysql Full text index on text field so users can search the site, but the problem is that they could search by arabic words and that doesnt work because its Multibyte, so is there a solution for that? or its just that i have to detect.....

if the search string contains 1 or more arabic letter
use SELECT * FROM `announce` WHERE `adtext` like '%ΚΡίνΘ%'
else
use SELECT * FROM `announce` WHERE MATCH(adtext) AGAINST('eng_word')

if i there is no solution other than detecting arabic letters, then please somebody tell me how to do that in PHP?

Thanks in advance