MT.Dialog - RadioElement Problem

gistfile1.cs

using System;
using System.Collections.Generic;
using System.Linq;

using MonoTouch.Foundation;
using MonoTouch.UIKit;
using MonoTouch.Dialog;
using System.Threading.Tasks;

namespace RadioButtonSample
{
  [Register ("AppDelegate")]
  public partial class AppDelegate : UIApplicationDelegate
  {
    // class-level declarations
    UIWindow window;
    Section rootSection;

    public override bool FinishedLaunching(UIApplication app, NSDictionary options)
    {
      // Setup initial conditions.
      window = new UIWindow(UIScreen.MainScreen.Bounds);
			
      // Create root view controller.
      var radioGroup = new RadioGroup(0);
      var root = new RootElement("Title", radioGroup){
        (rootSection = new Section("Foo"))
      };
      var dvc = new DialogViewController(root);

      // WORKS: Add items synchronously.
//      addRadios(3);

      window.RootViewController = new UINavigationController(dvc);
      window.MakeKeyAndVisible();

      // FAILS: Add some items on a background thread. 
      //      All items will be selected, and won't recieve click events.
      Task.Factory.StartNew(() => {
        BeginInvokeOnMainThread(() => addRadios(3));
      });

      // Finish up.
      return true;
    }

    private void addRadios(int total)
    {
      for (int i = 0; i < total; i++)
        addRadio("Item " + i);
    }

    private RadioElement addRadio(string caption)
    {
      var el = new RadioElement(caption);
      rootSection.Add(el);
      return el;
    }
  }
}