Multiplayer projectile problems!

I'm working on a game were you shoot projectiles. I have a simple script that makes a object move forward and if it collides with a player it sends an RPC call that makes him take damage. However when I shoot the projectile it deals 2 that damage. I know what causes this bug however I can't seem to figure out a solution. The bug is that when the projectile is created in everyone's game and when it travels forward and collides with a player every one sends a RCP call that says take damage. So if there are 5 people of the server the player will take 5 times the damage. Here is the code:

 var damadge : int;
 var damadgeOverTime : int;
 var damadgeOverTimeTime : int;
 
 var speed : float = 50;
 var size : Vector3;
 var gravity : float = 1;
 var gravity2 : AnimationCurve = AnimationCurve(Keyframe(0, 0), Keyframe(5, .5), Keyframe(10, 1));
 
 var aoe : boolean = false;
 var aoeDamadge : float;
 var aoeRadius : float;
 
 @HideInInspector
 var keepMoving : boolean = true;
 @HideInInspector
 var time : float;
 @HideInInspector
 var screenPos : Vector3;
 @HideInInspector
 var hit : boolean = false;
 @HideInInspector
 var guiDamadgeSpeed : float;
 
 
 function Awake () {
 
     time = Time.time;
 
 }
 
 function Start () {
 
     Physics.IgnoreLayerCollision(0, 8);
     transform.localScale = size;
 
 }
 
 function Update (){
 
 
 
 }
 
 
 function FixedUpdate (){
 
     if (keepMoving){
         
         rigidbody.MovePosition(rigidbody.position + (Vector3.Scale(transform.forward, Vector3(speed, speed ,speed)) * Time.deltaTime));
         rigidbody.position.y -= gravity2.Evaluate(Time.time - time) * gravity * Time.deltaTime;
 
     
     }
 
 
 
 }
 
 
 function OnCollisionEnter(collision : Collision) {
 
     if (collision.gameObject.tag == "Player"){ 
     
         var playerScript = collision.gameObject.GetComponent(Player);
         playerScript.networkView.RPC("TakeDamadge", RPCMode.All, damadge);
         Debug.Log("Hit player for" + damadge);
     
     }
     
     if (onHitEffect){
     
         var contact : ContactPoint = collision.contacts[0];
         var rot = Quaternion.FromToRotation(Vector3.forward, contact.normal);
         
         Instantiate(onHitEffect, contact.point, rot);    
     
     }
         
     
         Destroy (gameObject);
 
 
 }