Spawning enemies in multiplayer

I created an enemy for a multiplayer game, and it works fine, it chases the closest player and it can be killed. But now I want to spawn this enemies somehow.How should I do it? I tried this:

 var enemy : Transform;
 var delayTime : int;

 private var myReady : boolean = true;


 function Update ()
 {
     if(Network.isServer)
      {
     if(myReady)
     {
         networkView.RPC("Crear",RPCMode.AllBuffered);
     }
  }


    @RPC
    function Crear()
    {
       myReady=false;
 
       yield WaitForSeconds(delayTime);
       var myenemy = Instantiate(enemy,transform.position, Quaternion.identity);

           myReady=true;
    }

Its clear that it doesnt work, because when a player enters the enemies are alerady created in the server, but not for the new player. What should I do?

Thnx mates!