FeatureDataGrid zoom to selection

[DavidAshton]

I'm using the SDK example for FeatureDataGrid
http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#FeatureDataGrid

I have the FeatureDataGrid firing populating with selected polys or points.  It seems to work well with polys but when I populate the table with records of selected points it won't zoom to a selected point. 

Is there something I need to change to make the Option - Zoom to Selection, work with points?

Thanks
David

[JenniferNery]

This is related thread http://forums.arcgis.com/threads/13749-how-to-Zoom-to-point