In Reply to: Silly AA posted by Rick T on Tuesday, 13. April 2010 at 20:54 Bali Time:
Air Asia is an Asian airline. Citizens of countries like Indonesia, Thailand and Malaysian all carry government issued ID cards. The card number functions as a unique identifer.
The AA programmers were looking for a unique identifier to distinguish between passengers with the same name, which is very common in Asia. They decided to use passport numbers as the unique identifier.