[Mihai]

IOR is the nd setting in the maxwell dielectrics.

[tom]

i made tons of tests about this and 8etty also offered the same mental ray technique for such situations but i don't agree because it's not a good geometric approach in my opinion. instead, i prefer a global tolerance setting for behaviour of contact surfaces while shading.

[tom]

ILS, now I know the technique you mean very well. You must also model according to it. For example, you cannot make a liquid simulation with that technique. Where is in, where is out? no way.... Read more on this thread:
http://www.maxwellrender.com/forum/viewtopic.php?t=914
Maxwell needs more longlife implementations , not the weak fakes.