Pull To Refresh with Data Source

I have a DialogViewController and hooked up the RefreshRequested event. However the event does not fire if I set the TableView.Source property. If I do not set the datasource property then it works fine.

dialogView.RefreshRequested += HandleRefreshRequested;
dataSource = new ServerTableSource(dialogView.TableView);
dialogView.TableView.Source = dataSource;

This fails code fails to trigger the refresh event. No errors, just doesnt fire. Any ideas? Thanks!