XCSoar With LNAV?

Max and XCSoar Team

For the old Cambridge LNAV to achieve full functionality (i.e. automatic final glide calculation) it needs following sentences:
GPRMB standard NMEA sentence with Waypoint/GoTo info
GPRMC standard NMEA sentence with current location info
PCAIB Cambridge proprietary sentence with waypoint elevation info.

The format of the PCAIB sentence is:
$PCAIB,1,2,CRLF
1 Destination Navpoint elevation in meters, format XXXXX (leading zeros will be transmitted)
2 Destination Navpoint attribute word, format XXXXX (leading zeros will be
transmitted)

Normally these 3 sentences are provided to the LNAV from the GPSNAV/303 combination.

So, the questions a
Can XCSoar output these 3 sentences on a serial interface at 4800 Baud ?
Does that need to be a separate COM port or can this be output on the same COM port, where the input is used e.g for PowerFlarm data (GPS, Flarm and pressure data).

I am using an IPAQ310, which has only 1 wired external port, currently connected to PowerFlarm.
Personally I don't care about other data exchange with the LNAV, e.g. for sync of McCready setting.