Unity not recognizing Instantiate? JavaScript

I am trying to make a gun that shoots the bullets i made. Yet, when i finish the script i get one error...which is

"Assets/GUN/Shoot1.js(14,34): BCE0023: No appropriate version of 'UnityEngine.Object.Instantiate' for the argument list '(UnityEngine.Transform, UnityEngine.GameObject, UnityEngine.Vector3, UnityEngine.Quaternion)' was found."

Instantiate, for those who don't know, is for cloning objects. :D

Also this is the script...

 #pragma strict

function Start () {

} public var Bullet : Transform; public var bulletSpeed : float = 6000;

function Update () { if (Input.GetButtonDown("Fire1")) { if (!Bullet || !bulletSpeed){ Debug.Log("[Shoot] 'Bullet' or 'bulletSpeed' is undefined"); } else { var bulletCreate = Instantiate(Bullet, GameObject.Find("SpawnPoint"),transform.position, Quaternion.identity); bulletCreate.rigidbody.AddForce(transform.forward * bulletSpeed); }

}

}