Calling Function in other Script via Touch => iOS Crash

I´am porting a Standalone to iOS, at the moment I have problems with moving my code from GUI.Buttons to Touch.

I have a GameObject, with a guiTexture and a Script attached, that calls a function in another Script when the guiTexture is touched. If I touch the guiTexture the iOS App crashes, I´am not calling any fancy stuff in that other script it is just a Debug.Log.

 #pragma strict
 private var gui : GUITexture;
 
 function Start()
 {
   gui = GetComponent( GUITexture );
 }
 
 function Update()
 {
  if(Input.touchCount > 0)
   {
     for(var i : int = 0; i < Input.touchCount; i++)
      {
        var touch : Touch = Input.GetTouch(i);
        if(touch.phase == TouchPhase.Began && guiTexture.HitTest(touch.position))
         {
           var otherScript : TheOtherScript = gameObject.GetComponent(TheOtherScript);
           otherScript.CallMyFunction();
           Debug.Log("guiTexture Touched");
         }
      }
   }
 } 

And here the Function in "TheOtherScript" Script:

 function CallMyFunction()
 {
 Debug.Log("CallMyFunction executed");
 }