AddComponent can't find script name MouseOrbit?

i moved a folder with 2 .JS from angry bots demo to character customization demo. the scripts are CameraScript and MouseOrbit.

in Angry Bots, no errors,

and in Character Customization unity demo, i get error message that it cant find MouseOrbit script

NullReferenceException: Object reference not set to an instance of an object

this line:

 camera.main.gameObject.AddComponent(MouseOrbit)   ;

The MouseOrbit exists in both projects, and causes an error in just one, why, is it because its some kind of webplayer game parameters?

i reloaded the project and same error.