These new games utilize a new decryption method, and cannot be patched using Eboot Exchange 2.8. Some of the new games that cannot be patched by EE are:
* Iron Man 2
* Prince of Persia - Forgotten Sands
* Metal Gear Solid - Peace Walker
* FullMetal Alchemist
* What Have I Done To Deserve This, My Lord?
* Hexyz Force
Of course, there are methods to manually patch your games (UMDGen 4.0, etc), but these are rather complicated, especially when compared to the ease of Eboot Exchange. Another method to patch recent games is with the use of ISO Tool 1.51. Not only will it patch 6.20 games to work on the recent custom firmwares, but it does it right on the PSP: no PC required! Read more at OCModShop.