Blender Game Engine Z-BUFFER

Hi,i have a little problem with makehuman in bge, when i render everything is good,but in game i see teeth thro makehuman character, what can be a problem.
on makehuman forum ask for zbuffer, what is it and how to activate it.

Maybe a “wrong normals” problem?
Select all points and do Ctrl-N keys to “recalculate normals outside” or Ctrl-A keys to “Apply Scale”, maybe this will work…who knows?!

i will try this tomorow