[Q] geodetic spatial functions

Hi, I'm using Informix 9.30 with geodetic datablade (3.00). It seems that the geodetic spatial functions, e.g., distance, doesn't take the 3rd element of a point into account. The following is the script I tried with the result. create table test (location GeoObject); insert into test values ('GeoPoint((3,4,10),ANY,ANY)'); insert into test values ('GeoPoint((3,5,1),ANY,ANY)'); CREATE INDEX test_idx ON test (location geospcalt_ops) USING RTREE ; select location, distance(location, '((3,4,0),ANY, ANY)'::GeoPoint) fromtest; ## RESULT location GeoPoint((3,4,10),ANY,ANY) (expression) 0.00 location GeoPoint((3,5,1),ANY,ANY) (expression) 111167.9466418 If the 3rd element is considered, the distance between (3,4,0) and (3,5,1) should be closer than that between (3,4,0) and (3,4,10), but it seems that this is not the case for geodetic distance function. I'm wondering if this is true that the geodetic spatial functions doesn't consider the 3rd element in the point or if there is something that I'm missing here. Any comments would be appreciated. Thanks in advance, Kiyoung..