attached.Rigidbody isn't working with a ChactacterController?

I'm trying to make my player jump with "rigidbody.AddForce". I have a charactercontroller and a rigidbody on my player.

First I tried just using "rigidbody.AddForce", but nothing happened.

var jumpSpeed : float;

function Update () {

 if(Input.GetButton("Jump")) {

     rigidbody.AddForce(0,jumpSpeed,0);
 }

}

Next I tried using "collider.attachedRigidbody.AddForce", but still nothing is happening.

var jumpSpeed : float;

function Update () {

 if(Input.GetButton("Jump")) {

     collider.attachedRigidbody.AddForce(0,jumpSpeed,0);
 }

}

Am I missing something?