CHANGE_CONFIGURATION's protection level definition has modified in Jelly Bean 4.2.
If you are allowed to use development tools, you can manually grant permission with the 'pm' command.
Should you have SuperUser rights on your device, the MoreLocale 2 app may obtain the permission automatically.
You will be able to choose from many locations with this app.
Should your locale not display, you can use the menu's custom locale option.