FPS Tutorial AI Damage not Working

I used a video tutorial adapted from the unity fps tutorial, which can be found at http://www.youtube.com/watch?v=xpSi7oBe4pk&feature=related but the AI is taking no damage. It comes up with this error:

The referenced script on this Behaviour is missing! UnityEngine.Object:Instantiate(Object, Vector3, Quaternion) Rocket:OnCollisionEnter(Collision) (at Assets/FPS_Tutorial_Completed/Assets/WeaponScripts/Rocket.js:16)

A link to my scene is here:http://www.mediafire.com/?pc6epx8ot1o19n3

PLEASE HELP!

did you download the FPStutorial_zip? if so than all you have to do is type in rocket in your project search panel and their should be a script called rocket. but you probably figured this out already.