I have a user who has changed the input language to Arabic and then has locked his device and now when he tries to input his password in english, he cant as it is now typing in Arabic!!!
How about you get him to enter his password in a translator for Arabic and then type that in for the password. Once you're in, simply change the language on it through Options.... then delete all the other languages off the phone.
Just saw a fix for this.... Holding down the ALT key and then hitting ENTER will take you through a list of languages installed on the unit. You can then change back to English. I haven't tried it. Just read it on another forum today.
also as a foot note. I have removed all the languages that are not going to be used but if the combination of alt+enter are pressed, the device goes into input language change option and chooses the 1st language on the list (which is Arabic) and then option then goes off the screen!!! The device then displays a message to disable this shortcut, but leaves the language in Arabic. The only way to disable this is to wipe the device and then reinitialise it on BES and go into the device and disable the change language shortcut (but make sure your language is set to the one you want first)