Hmm....
That shouldn't happen.

May I suggest you try an experiment?

Clear the figure's textures in the relevant area (so there's no skin texture), then colour her a very bright red in diffuse only (set everything else to black/0).
Do the same again, except using bright yellow instead of red.
Do NOT change the lighting or anything else - I'm very curious about this 'cos as I said, it shouldn't happen.

Post the results. We'll take it from there:-)

(Afterthought - I'm not sure you should be worried about it anyway. OK, so it works slightly differently on different figure textures - but who's going to know? I didn't.. I thought it was a lighting effect..)
Errm.. What type of lighting set-up are you using anyway?

(Diolma is retiring for tonight - be back tomorrow)

Cheers,
Diolma