How to convert 3d dxf contour map to nurbs surface

A friend wants to convert a 3d dxf contour map (of the local geography) to a NURBS surface so he can make so rapid prototype models. I've tried bringing the data into SolidWorks 2008, but it brings SolidWorks to a grinding halt.

Any suggestions on what software could do this?SolidworksSurfacing