[GRASS5] G3D-api error

[N.J. Hardebol]

Hello,

I'm writing a geophysical routine and I'd like to store a 3D temperature
field as G3D raster.
In the past I encountered some problems to find all the includes and lib -
this is properly solved.
I'm using Grass5.0.2 under Suse Linux 8.2

but,

I'm not succeeding in writing my data to a g3d file.
I'm using the following functions (and some more..):
G3d_openCellNew (char *name, int type, int cache, G3D_Region *region); that
returns a void* which is a pointer to the newly created g3d-raster - Am I
right?

G3d_putValue (void *map, int x, int y, int z, char *value, int type); where
void *map revers to the opened g3d-raster

my g++ compiler tells me that *map should be of type G3D_Map instead of
void*.

checking the grass5.0.2/src/include/G3d.h confirms this with the following
function declaration:
int G3d_putValue(G3D_Map *, int, int, int, char *, int);

What am I doing wrong? - Or do some inconsistencies exist in the g3d-api?

with kindest regards,

Nico