I am using the SL unit test framework for tests (http://code.msdn.microsoft.com/silverlightut). My code is heavily client-server communications dependant, and I access the GUI dispatcher in several places to make sure important data is only accessed on a single thread (ie. the GUI thread).

This dispatcher seems unavailable in the unit tests - I have tried using Deployment.Current.Dispatcher and even created an instance of a blank control to try use its own dispatcher, but both don't work. The code inside of Dispatcher.BeginInvoke() just never executes, even if I include a Thread.Sleep afterwards.