Yeah if you jailbreak your phone it lets you change all sorts of settings. If you are on the latest iOS 6 I'm not sure if there is a jailbreak available yet....might be.
There is a jailbreak for ios6 but I wouldn't touch it untill it is an unteathered version
A jailbreak for ios 6 has been developed but because it's a tethered version if you need to reboot or Respring (for instance after installing an app or tweak) you will need to connect it to your computer and run a program to force it to reboot.The same if your computer dies.No worth the hassle untill the full working 'unteathered' versionI think the prase teathered comes from being 'tethered' / tied to your laptop top cause you regularly need your laptop to restart your phone.
Tethered jailbreak is a jailbreak which every time you restart of shut down it will go into recovery then you have to launch the program you jailbroke it with and it should reboot it.