Missing PropertyDescriptor value on ListChangedEventArgs with BindingList in MonoTouch

BindingListBugTest.cs

using System;
using NUnit.Framework;
using System.ComponentModel;

namespace BindingListBug
{
	[TestFixture]
	public class BindingListBugTest
	{
		string changedPropertyName = string.Empty;
		bool isEventRaised = false;

		[SetUp]
		public void SetUp ()
		{
			var persons = new BindingList<Person> ();
			persons.Add (new Person (){ FirstName = "Stefaan", LastName = "de Vogelaere" });
			persons.Add (new Person (){ FirstName = "Christophe", LastName = "De Langhe" });

			persons.ListChanged += (object sender, ListChangedEventArgs e) => {
				isEventRaised = true;
				if (e.PropertyDescriptor != null)
					changedPropertyName = e.PropertyDescriptor.Name;
			};	

			persons [0].FirstName = "Stefan";
		}

		[Test]
		public void IsEventRaised ()
		{
			Assert.IsTrue (isEventRaised);
		}

		[Test]
		public void DidWeReceiveChangedPropertyName ()
		{
			Assert.AreEqual ("FirstName", changedPropertyName);
		}
	}

	public class Person : INotifyPropertyChanged
	{
		private string _lastName;
		private string _firstName;

		public string FirstName {
			get { return _firstName; }
			set {
				_firstName = value;
				OnPropertyChanged ("FirstName");
			}
		}

		public string LastName {
			get { return _lastName; }
			set {
				_lastName = value;
				OnPropertyChanged ("LastName");
			}
		}

		public event PropertyChangedEventHandler PropertyChanged;

		protected virtual void OnPropertyChanged (string propertyName = null)
		{
			PropertyChangedEventHandler handler = PropertyChanged;
			if (handler != null)
				handler (this, new PropertyChangedEventArgs (propertyName));
		}
	}

}