Sony faced a setback in its campaign to control what software can run on its PlayStation 3 after hackers published one of the cryptographic keys that forms the core of the security scheme locking down the game console.The so-called LV0 key, released by a crew calling itself "The Three Tuskateers," grants access to the one of the most sensitive parts of the PS3. Its availability should make it easier for hackers and modders to work around restrictions Sony places on the console. The key can be used to decrypt future security updates Sony issues for the console and to incorporate those changes into custom firmware packages not authorized by the