[Test] public void AddToBadUnits()
		{
			Duration d = new Duration(5,(Duration.Unit)2000);
			d.AddTo(new DateTime(2000, 1, 1));
		}
		[Test] public void AddToMonths()
		{
			Duration d = new Duration(5,Duration.Unit.Months);
			Assert.AreEqual(new DateTime(2000,6,1),d.AddTo(new DateTime(2000,1,1)));
		}		
		[Test] public void AddToWeeks()
		{
			Duration d = new Duration(3,Duration.Unit.Weeks);
			Assert.AreEqual(new DateTime(2000,1,22),d.AddTo(new DateTime(2000,1,1)));
		}				
		[Test] public void AddToDays()
		{
			Duration d = new Duration(5,Duration.Unit.Days);
			Assert.AreEqual(new DateTime(2000,1,6),d.AddTo(new DateTime(2000,1,1)));
		}