Firstly set ure xbox clock to GMT-12 hrs; Load up the game to the title screen and then press ure middle button to go back to the xbox dashboard - go to the clock again and then select +14 hours (just push up from the -12 hrs),press B and then load up the game again - now go back to the beginning of this post and repeat. Once you have done this 100 times it will unlock on loading up. You do not have to do this all in one go, I did 10 a day for 10 days and it unlocked just make sure you keep on adjusting the clock - I just unlocked it today so it does work