Zita i believe what you did is converted the char encoding to UTF-8, this is nothing but when the arabic language displayed in the browser, the browser need to know in which encoding it has to be displayed...
But this is nothing to do with translation if i am not wrong ???
Do you simply want to change the English letters into Arabic? You could try mapping from English letters to Arabic, but remember that some English letters are read in groups, eg SH, TCH, STR (as in construction and instrument) and that is difficult to transliterate.