How to set up aliases for an french /arabic site

Hello everybody
I've a multi lingual site in french and arabic, currently using pathauto 6.x-1.5 with an i18n-ascii.txt file
with (or without ) transliteration the arabic urls are unreadable and useless
is there a way to keep the french aliases with the ar prefix for translated arabic pages ?

like it's done in many sites: amensty international, france 24

Thanks taking time to reply