Unit Test And EntityManager.SaveChanges

   I'm trying to write a test and I'm running into an issue if I call SaveChanges on the EntityManager object.  
I get the following Exception:

"IdeaBlade.EntityModel.EntityManagerSaveException: This EntityManager is not currently connected - Reconnect before attempting to save."

Am I missing something or is there a work around for this.  My DomainModelEntityManager class extends from EntityManager and I pass in false to the constructor so that it can run disconnected.

        [TestMethod]
        public void TestMyMethod()
        {
            var mgr = new DomainModelEntityManager(false);
            var myObject = new MyClass { ID = 1};
            mgr.AttachEntity(myObject);
            var myService = new MyService(mgr);
            myService.PerformLogicAndSave(myObject);
        }
       public class MyService{
              public MyService(EntityManager myManager){
                     MyManager = myManager;
              }
              public void PerformLogicAndSave(MyClass myObject){
                     //Do Something to myObject
                     MyManager.SaveChanges();
              }
       }