you can do this...
Hello !
Well, I know this problem. The method you can do, is simply that:
1. select the isoparm on the outside
2. Edit Curves-->Duplicate Surface Curve
After that you will have a copy from the outer isoparm on the surface. Don´t move it.
Now, select this new created curve.
Right Mousclick --> Curve Point. Select one direct on the new curve. The point is yellow.
After that-->Edit Curves-->Detach Curves.
This will produce two independent curves. And if you will select both, you can make a loft.
ciao,
bernhard
contact me via MSN: rieder@utanet.at