Collision Detection

Hello, I asked a similar question earlier and got many helpful responses. My script no longer has errors but neither does it work.

alt text

The script is supposed to detect when the sphere in the screen shot hits the cube and remove both. However it actually does nothing and I get no error messages. Help would be very much appreciated.

var wall : GameObject;

function OnTriggerEnter (col : Collider) { Destroy (gameObject); Destroy (wall);

}

Check that the sphere has a trigger collider and a rigidbody attached

The script looks fine otherwise