http://cod7ops.blogspot.com/
http://fileups.net/1h6i79
Steps
1st
Download the 15th Prestige Hack Files to your PC And Pulg USb Flash Drive.
2nd
Extract Download file using WinRar and Copy it to your Usb Drive.
3rd
You put the usb storage device in the PS3, go to the Saved Data Utility option in the Game area and copy 15th Prestige Hack file form USB to Saved Data Utility Area ..
And its all, if u have any questions, pm me.
If u dont know how to download - http://scdownloads.za.pl/tut/us.html