It only works with the 2D version. You have to open the gearhead.cfg text file (which doesn't appear until after you run the gearhead executable at least once) and then uncomment (remove the # symbol) the NAMESON line.
Personally, I like to use the minimap (uncomment the MINIMAPON line). It works in both the 2D and the 3D versions. I only wish that it used different colors to represent friendlies and hostiles.