[GRASS-user] z coordinate not taken

[gmail account]

Hello,
I have a raster map (part of Sicilia island) with all the three 
coordinates. However, when I importe it, Grass only see a 2D map.
The command r.category seems to detect the 3th coordinate.
Please, do you know how can I import the vertical coordinate from the 
raster already imported from a file in a .adf format?
I imported to grass via gdal. Is there any other mean to import an .adf 
file, which allows the user to import the vertical coordinate?

Thanks,
Gustavo