Ok, someone tell me what I'm doing that's stupid.
I just compiled the latest plib based simgear and flightgear from cvs. When I run the executable, the splash screen pops up momentarily and FlightGear exits with the following message:
Unknown line(#867) in file: 00 12835 SALT LAKE CNTR
This is running with the latest cvs data branch.
Curtis Olson: http://baron.flightgear.org/~curt/
Unique text: 2f585eeea02e2c79d7b1d8c4963bae2d