Collision Problem

I got a box that suppose to get destroyed when it collides with the First Person Controller.

I get an Error: Script error: OnCollisionEnter This message parameter has to be of type: Collision The message will be ignored.

What am I doing wrong? I put the script on the box. When the FPC touches it nothing happens.

 function OnCollisionEnter (theCollision : Collision)
 {
 if (theCollision.gameObject.name == "First Person Controller")
 {
 Destroy (gameObject);
 }
 }