Problem exposing public variable to Inspector in C#

Hi

I've looked through the posts with a similar problem, don't seem to deal with what is happening here, well if they do trying the solution proposed hasn't worked.

I am putting in a public string variable that I wish to expose to the inspector. Basically I am changing a NGUI script putting in the variavle 'public string objectTagName' as follows.

[AddComponentMenu("NGUI/Examples/Drag & Drop Surface")]

public class DragDropSurface : MonoBehaviour {

 public bool rotatePlacedObject = false; 
 public string objectTagName;
 
 
 void OnDrop (GameObject go)
 {
     DragDropItem ddo = go.GetComponent();
     
     if (ddo != null && ddo.tag == "Player")
     {
         GameObject child = NGUITools.AddChild(gameObject, ddo.prefab);

         Transform trans = child.transform;
         trans.position = UICamera.lastHit.point;
         if (rotatePlacedObject) trans.rotation = Quaternion.LookRotation(UICamera.lastHit.normal) * Quaternion.Euler(90f, 0f, 0f);
         Destroy(go);
     }
 }

}

I don't normally use C# and know nothing of it's little peculiarities. Don't quite understand why this is not showing though, should be straightforward. Am I missing something? Any assistance would be greatly appreciated.