Multiple UV map issue

Hello Guys,

seem to have been a bit lapse as of late but i have run into some issue with a new model i have started (and actually intend to finish).
basically i have two UV maps, one for the head and one for the body, the irrelevant vertices are welded and pinned outside of the texture area for both. (obviously the body doesnt appear on the head unwrap etc.).
I did a bit of sculpting on the mesh and baked the appropriate textures out for each.
after applying both normal maps it causes some real issues during the render.

from what I can see it appears to be forcing both maps to occupy the same space when in reality because of the seperate UV maps it shouldnt be the case. I have double checked that both textures are set as normal tangent maps with influence only on the normals. Finally also checked that each texture is mapped to the correct uv map so head to head and body to body.

really baffled, dont think its anything obvious but any help is appreciated :slight_smile:

I have attached a couple of images to help explain the problem.

blender 2.61