Command Objects executed with BeginExecute are not Async (4.5.24-RC)

I am using the DataPortal_Execute methods in my command objects.  I call them from the Command's Factory Method:

DataPortal.BeginExecute(Of MyCommandObj)(cmd, callback)

I call the Factory Methods from a ViewModel (WPF) using a Lambda expression for the callback.

The code never runs as Async.

I am not sure if this is a bug or if I don't know what I am doing, but if I change this code in the DataPortalT.cs in CSLA, it works:

This code change is in the BeginExecute(T command, object userState) method.

 var result = await DoUpdateAsync(command, false);   *** I changed the isSync parameter value to False ***

Am I on the right track here?

Thanks for your help.

Ben