You can also just delete the patch on your JB PS3, make sure your JB PS3 is not connected to the internet, start MW2 and start a split screen match, then quit the game, connect your ps3 back to the internet and transfer your 1.12 patch, disconnect the internet again and start MW2. This is if you want to test patches off the disc and not create a backup. This is what I do to test patches.