It sounds like you're using the version of the exported that comes with blender. I didn't have much luck with that. I've had the most luck with the blender2cal3d_2.py file that comes with recent versions of cal3d.
You can check my post in
http://community.crystalspace3d.org/forum/index.php/topic,283.0.html for a link to get it as well as my patch or just browse the CVS for cal3d at sf.net and grab the file if you want a pristine copy.