如何在Silverlight UserControl中引用我添加到DataPager的ControlTemplate的TextBox？

Using the Silverlight 3 Release, I created a Silverlight UserControl that contains a DataPager and a DataGrid. I modified the DataPager ControlTemplate and added a TextBox with an x:Name of TestTextBox inside the DataPager's Border right before the standard DataPager buttons, but I can't seem to get a reference to that TextBox in the UserControl code behind.Using the Silverlight 3 Release, I created a Si