Damage on collision with player..

I have been working on a script for my Enemy AI that I want to lock onto the player, chase it and if it collides with it deals damage to the player. as of right now it is locking on and chasing just fine but when it collides it is not dealing damage. Any idea what I did wrong? (also if any advice can be given as far as to put a timer on how often the collision damage can occur that would be great)

UPDATED SCRIPTS

Enemy Parent

 var HP = 100;
 var runSpeed : float = 5;
 var target : Transform; 
 
 private var controller : CharacterController;
 
 var isChasing : boolean;
 var seeDistance : float = 20;
 
     function Awake(){
     
     controller = transform.GetComponent(CharacterController); 
 
     var playerCount : int = Network.connections.Length +1;
     }     
 
     function Update () {
         
     var tempTarget : Transform = GameObject.Find("Player").transform;
         if (!target){
             if (tempTarget){
             target = tempTarget;
             }
         }
         
     if (target) {     
         var forward : Vector3 = transform.TransformDirection(Vector3.forward);        
         
         transform.LookAt(target);
         transform.rotation.x = 0;
         transform.rotation.z = 0;
         controller.SimpleMove(forward * runSpeed);
         
         var gos : GameObject[];
     gos = GameObject.FindGameObjectsWithTag("Player"); 
     
     var thePlayer:GameObject = gos[0];
     var dist = Vector3.Distance(thePlayer.transform.position,transform.position);
     
     if(dist<seeDistance){
         isChasing= true;
     } else {
         isChasing=false;
     }
         
         }
     }
     
     function ApplyDamage (damage : int) {
         HP -= damage;
         
         if (HP < 1){
             Die();
         }
     }
 
     function Die(){
         Destroy(gameObject);
         gameObject.Find("Player").SendMessage ("Heal", 10);
     }
     
     @script RequireComponent(CharacterController)

Enemy Child

 var damage = 10;
 var hitDelay : float = 0.5;
 private var nextHitAllowed : float;
 
 function OnTriggerEnter (col : Collider) {
     if(col.gameObject.tag == "Player"){
         if(Time.time > nextHitAllowed){
             SendMessage("ApplyDamage", damage, SendMessageOptions.DontRequireReceiver);
             nextHitAllowed = Time.time + hitDelay;
     Debug.Log("Hit Player");
         }
     }
 }

Player Script (the one that deals with health and death)

 static var health : float = 100;
 var maxHealth = 100;
 var degen : float = 1;
 
 
 function Update(){
 
         ApplyDamage(degen*Time.deltaTime);
         HealthManager.hitPoints = CharacterDamage.health;
     }
 
 
 function ApplyDamage (amount : float){
 
     health -= amount;
     if(health < 1)
         Die();
 }
 
 function Die(){
     Application.LoadLevel (0);
     }
 
 function Heal(points : float) {
     health = Mathf.Min(100.0, health + points);
     }

Edit Note : Also I noticed that my line CharacterDamage.health += 10; allows for the health value to go over 100 (I assume simply by increasing the number rather then healing? What would I need to do to fix this? I am assuming it is something along the lines of SendMessage("Heal", 10.0, SendMessageOptions.DontRequireReceiver); and adding a heal function to the player?

thanks in advance.

Update : After using Debug.Log I have realized that there is no collision being detected and I have no reason why. Any thoughts on this may solve the issue of not taking damage.

Update 2 : I have solved the healing upon enemy death but can still not get the collission to be detected to apply damage.