[mkgmap-dev] Time Zones in the USA defined or not?

I was looking at Administrative boundarys in INDIANA, trying to find if TIME ZONES are defined in the OSM. There is a linetype '0x19 Time Zone' defined and I would like to add it to my maps (huge red thick line, so you are aware you are passing the zone) I don't think this is defined in the USA Is anyone using linetype 0x19? Greg