It is debatable whether this is correct in the general case.
There's nothing really wrong with 0xFFFF logically.
Burnout Paradise however bases its in-game language on this and does not recognise 0xFFFF.
The game uses Japanese in the default case.
I've avoided the "rest of Asia" code since Burnout Paradise seems to use a different value (0x01F8) for that than what I expected (0x01FC).