The wind estimation if finally integrated in the first beta release. You can download the firmware for XC Tracer II (XC_Tracer_II_R07_RC06.iap) and XC Tracer Mini II GPS (XC_Tracer_Mini_II_GPS_R03_RC04.iap) from here.
In the config file there is a new entry called LXWPW. It is basically the LXWP0 sentence, with the wind information added:
$LXWP0,logger_stored, airspeed, airaltitude,vario,,,,,, hdg, windspeed*CS
0 loger_stored : [Y|N]
1 TAS [km/h]
2 baroaltitude [m]
4-8 not used
9 heading of glider
10 windcourse [deg]
11 windspeed [km/h]
This is a beta release for testing, there may still be bugs in the code, and many apps do not yet accept external wind.