How do I change my 3D Text Value when triggered?

In my game I am developing I attempted to add a script which would change my 3D text value when triggered. Got 2 errors though... :-(

My Code looks like this:

function OnTriggerEnter( hit: Collider)

{

if(hit.gameObject.tag == "Test")

{

var a=GameObject.Find("New Text");

a.GetComponent(TextMesh).text="a";

}

}

But I got an error that said this:

'text' is not a member of UnityEngine.Component'.

When I tried to bypass this I also recieved another error which said something like this (not exact):

Unity Exception. Variable cannot be declared in this function.

Does this have to do with it being Unity iPhone?

Please help by posting a better piece of code or by explaining what is wrong. Thanks alot! :D

On iPhone you can't do dynamic typing, so you need to do something like this:

var textMesh : TextMesh = a.GetComponent(TextMesh);
textMesh.text = "a";