Mudbox double sided mesh problem


#1

Hello. I am trying to Freeze the inside of a double sided mesh so that when I add sculpt detail to the outside faces the sculpt brush does not affect the mesh faces on the inside of my mesh.
As you can see the 1st image shows part of the inside faces painted with the freeze tool.

The 2nd images shows the freeze tools has also frozen the outside faces. I do not want the outside faces frozen just the inside. I know in Zbrush it is easy to section of the polygon groups to avoid this kind of problem. But I have looked everywhere for a solution to this problem with no joy :banghead: