for an inverted normal, you would likely see a hole or a big black spot. Plus, in your modeller, you can have an inverted normal and still see it if its a forced 2 sided material. In this case, it looks more like you have an unwelded veritice somewhere in that general area or a misaligned face that is very dificult to see in the modeler but appears when you render in poser ( do to such a smaller scale usually) There was an earlier post in the forums with someone who had the same problem a while back, and he managed to fix it, I'll see if I can find it.