Getting the coordinates of a PivotItem when using the Silverlight PivotViewer control with Microsoft Live Labs Pivot

Question

I'm using the Silverlight PivotViewer control in an application I'm writing to display Microsoft Live Labs Pivot content through Silverlight. In my app, I want to handle right-clicks on items and return where inside the image the click occurred.

I've already implemented the necessary event handlers and the process of finding which image was clicked, but I haven't found a way to find where inside an image the click occurred. Is there a direct way to find this out?

If not, I will need to use where the click occurred on the control (obtained from the event handler) and where the image is located inside the control. How can I obtain the coordinates of a PivotItem inside a PivotViewer Silverlight control?