UnityScriptはstaticなプロパティができない

http://wiki.unity3d.com/index.php/AManagerClass#Javascript_-_AManager.js

UnityScriptだけなぜかプロパティがない・・。
このようにプロパティ版で書きかえてみた。
「public static function get instance():AManager {」が具体的な箇所

#pragma strict

import System.Collections;

public class AManager extends MonoBehaviour
{
    /// AManager is a singleton.
    /// To avoid having to manually link an instance to every class that needs it, it has a static variable called
    /// instance, so other objects that need to access it can just call:
    ///        AManager.instance.DoSomeThing();
    ///
    private static var s_Instance : AManager;
    public static function get instance():AManager {
        s_Instance =  FindObjectOfType(AManager);
        // This is where the magic happens.
        //  FindObjectOfType(...) returns the first AManager object in the scene.
        if (s_Instance == null)
            Debug.Log ("Could not locate an AManager object. \n You have to have exactly one AManager in the scene.");

        return s_Instance;
    }

    // Ensure that the instance is destroyed when the game is stopped in the editor.
    function OnApplicationQuit() {
        s_Instance = null;
    }
}

このようにして、継承し，

public class Manager extends AManager {
}

このように使ってみるが、

private static var _aManaget:AManager;
_aManaget = Manager.instance;

staticつけてるのにプロパティがstaticだと認識されない・・・

BCE0020: An instance of type 'AManager' is required to access non static member 'instance'.

ここでも書けないぞって言ってやり取りがある。
URL:http://forum.unity3d.com/threads/99568-UnityScript-Getter-Setter-Are-they-supposed-to-work