CharacterController touch ground

Hi, I have a GameObject named CharacterJig, and I am dropping this script on it:

private var charController : CharacterController;

function Update()
{
    charController = GetComponent(CharacterController);
    if (charController.isGrounded)
    {
    }
}

Though, during play I get this error:

MissingComponentException: There is no 'CharacterController' attached to the "CharacterJig" game object, but a script is trying to access it.

If I remove the If statement, it does not error. What is wrong with this code? I am simply trying to get the game to detect if the game object is touching the ground.

in the hierarchy, select the CharacterJig gameObject, select the "component" drop-down-menu, physics, and select Character Controller