Project "Expression.Samples.Interactivity.Design.SL" references WPF DLL?

Mar 11, 2010 at 7:03 PM

The Expression.Samples.Interactivity.Design.SL project makes a refence to System.Windows.Interactivity located in the WPF folder.  Should this not be a reference to the equivalent file located in the Silverlight folder?  If the current assembly is the correct one, then why is this the case?