Silverlight: spatial reference issue

I am using Visifire diagrams to display data in a Windows Phone 7 application. I created a diagram that was properly bound to a dependency property. It worked great. I decided to turn the chart into a custom control since I was going to use it in another project and also with the same setup. Now my data binding doesn't work unless I bind it in code, not XAML.

here's what i have:

<UserControl ... x:Name="root">
 ...
     <chart:DataSeries ... DataSource="{Binding ElementName=root, Path=Results}">
 ...
</UserControl>

      

        
        
        
      

    

and the code behind:

public MyList Results
{
    get { return (MyList)GetValue(ResultsProperty); }
    set { SetValue(ResultsProperty, value); }
}

    // Using a DependencyProperty as the backing store for Results.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty ResultsProperty =
        DependencyProperty.Register("Results", typeof(MyList), typeof(MyChart), new PropertyMetadata(null));


public GoogleChart()
{
    Loaded += delegate
    {
    //  theChart.Series[0].DataSource = Results;
    };
    Results = new GoogleResults();
    InitializeComponent();
}

      

        
        
        
      

    

If I uncomment the line theChart.Series[0].DataSource = Results;

it works fine. But if I leave that line commented out (for example, before I moved the diagram to the UserControl), it doesn't link. (By the way: theChart

is the x:name

parent of the chart, so the first item .Series[0]

refers to the chart).

Does anyone know why this is happening? Again, it worked great until I moved the code to UserControl.

thanks