DXF/grass

[Gareth Morris]

Dear sir/madam,

 I have recently started a PhD related to the effect 
of varying surface processes on mountain belt development in the 
Pyrenees. An essential component of this particular project is a 
topographic database. I have digitised contour maps in Geocad and 
imported them into Surfer as .cnt files. However, I am experiencing 
problems when I attempt to import the data as DXF files into 
Grass4.1. That is, Grass4.1 does not appear to recognise the 
z-values. 
At present DXF is the only format that I can use until ERmapper 5.0 
is installed from which I should be able to import/export in 
various formats.
Is there a command/route I can use with my DXF files so that grass 
recognises the z-values? To relabel my contours in v.digit is 
impractical given the resolution of the data. 
Thank you very much for your time and help,

Gareth Morris
email:- RGM542 at bham.ac.uk
School of Earth Sciences
University of Birmingham
United Kingdom