splines and tangencies

ok.

Does this bug anyone else?

I have created a cam, and used splines to create a good portion of the surface.

Now, I was planning on giving the guy making the cam a few reference points so that we could check the thing. I give a dimension from the "center" of the cam to the center of a follower, which is tangent to the cam. ie: at

Anywho, it turns out that you can't make a sketch object tangent to a spline.

So I can't give the guy any reference dims over a majority of the cam surface (I did use arcs in a few areas).

What's really mucked up, is that I *CAN* do a tangent mate or a cam mate to the cam surface.

So why the heck can't I draw a sketch circle and make *IT* tangent to the spline?

Anyone?

Bueller?

-nick e.