I did a little more Googling after I posted this and it turns out there's an app called CaptionCrunch and at some point the developer created a special request version that's specifically for changing/reverting the carrier string. It was released before iphone system 2 but it still works. It does hang for a while with a "please wait" message but it eventually gets past that and allows you to revert to the official carrier string or set a different one if you like.
If anyone's interested, it can be downloaded from
macdaddyworld.com.
Oh....and no jailbreaking required for this. It's a Mac app and it syncs with your docked iphone.
Oh....and no jailbreaking required for this. It's a Mac app and it syncs with your docked iphone.