TIdIOHandlerThrottle & TIdMappedPortTCP

When using a TIdMappedPortTCP


why does neither of these methods work and what should I do instead?

1:
procedure TForm1.MappedPortOutboundConnect(AThread:
TIdMappedPortThread; AException: Exception);
var
    IdIOHandlerThrottle: TIdIOHandlerThrottle;
begin
    IdIOHandlerThrottle := TIdIOHandlerThrottle.Create(nil);
    IdIOHandlerThrottle.ChainedHandler :=
AThread.OutboundClient.IOHandler;
    AThread.OutboundClient.IOHandler := IdIOHandlerThrottle;
    AThread.Data := IdIOHandlerThrottle;    //Freed with AThread
end;


2:
procedure TForm1.MappedPortConnect(AThread: TIdMappedPortThread);
var
    IdIOHandlerThrottle: TIdIOHandlerThrottle;
begin
    IdIOHandlerThrottle := TIdIOHandlerThrottle.Create(nil);
    IdIOHandlerThrottle.ChainedHandler :=
TIdIOHandlerSocket.Create(IdIOHandlerThrottle);
    AThread.OutboundClient.IOHandler := IdIOHandlerThrottle;
    AThread.Data := IdIOHandlerThrottle;    //Freed with AThread
end;