now it works.
Oddly, on TomTom you must not select a bluetooth device, even if it is bluetooth. Rather you should choose "other wired NMEA gps" even if there is no wire at all. This way, you get a window that lets you choose among all the bluetooth devices you have paired, so you choose GPS device and it is done.
It works wonderfully, it is very fast in 3D and speaks clearly in many languages in real time.
Just this use is a good reason to own my netbook pro