Papervision3D question

How do you access the contents of a Material that has been added in Papervision? Tried getMaterialByName, but it isn’t working…

Essentially what I need to do is access the MovieClip that I added as a MovieMaterial. I need to be able to turn on and off some layers on rollover. I have no problem accessing the plane on a rollover, but can’t seem to access the materials that make up said plane.