public override bool IsContextOK (Context ctx, IConstructionCallMessage msg)
		{
			SyncContext sctx = SyncContext.GetContext ();
			if (sctx == null || (sctx.GetType() != contextType)) {
				syncContext = (SyncContext) Activator.CreateInstance (contextType);
				return false;
			}
			else {
				syncContext = sctx;
				return true;
			}
		}
		public SyncContextDispatchSink (IMessageSink nextSink, SyncContext syncContext, MarshalByRefObject ob)
		{
			this.nextSink = nextSink;
			this.syncContext = syncContext;
			target = ob;
		}
		public static void SetContext (SyncContext ctx)
		{
			context = ctx;
		}