Linked curve duplicate with separate Geometry settings, possible?

I have a bezier curve, that has a front and a back, little bit of Extrude and a little bit of Bevel. I’m trying to make a second bezier curve that would be linked to the original, mut only thing linked would be the actual shape of the curve, I would need it to have no front or back, and different Extrude and Bevel settings. But it seems there is no way to unlink these geometry settings, or is there?

I’m using Blender 2.58.1.

The extrude and bevel are part of the curve. A font is a curve. So to have separate versions, you need two curves. But the text of the font can say the same thing. This is typically how capping is done. It also allows you to have different materials on different parts of the font.