OCX and GPS navigation with Mappoint

Hi,
I developed a software with visual basic 6, I would use
"Driving guidance panel with voice commands, but did not find any basis to start this.
Use these commands:

Set objMap = mappoint1.NewMap(geoMapEurope)
Set objRoute = objMap.ActiveRoute
objRoute.Waypoints.Add objMap.FindResults("roma").Item(1)
objRoute.Waypoints.Add objMap.FindResults("milano").Item(1)
objRoute.Calculate

**** Up to this point everything OK *****
How do I start with voice commands navigation?
I have a GPS receiver through COM1 with commands NMEA

Please help me:49v:
Thanks to all
Alex