RigidBodyDrag Script help

Hello fine unity people.

I am fairly new to UnityScript though im certainly making some headway now. I am puzzled by a few issues I am having so i have decided to put them to the community. This being the first.

I am using the DragRigidBody script that comes with the standard assets. I have attached this to a few assets in game that I want the player to move.

However the script is also influencing Rigid bodies in the scene that do not have this script attached. Is there any reason for this? and how to I stop it?

Thanks in advance for your replies.

anyone know how to do this?