> 
> Anyway, I thought that when the terms "longitude" and "lattitude" were
> used, one was always refering to the "traditional" system (someplace
> in Greenwich at longitude 0, the equator at lattitude 0; I don't know
> where they place the center of the earth for defining angles phi & theta).

For a discussion about why there are multiple lat/long systems try:
http://www.gps.gov.uk/guidecontents.asp

	David

-- 
David Laight: david@l8s.co.uk