If you're using Victoria, the problem is probably because she has, I guess it's a cornea, in front of the rest of her eye to produce better reflections... in a shaded, or textured views, you can see through it if it's set invisible... I'm not sure if you can do that with cartoon view... I think the actual material is the one set for "eyeballs", see if that's made invisible, if it is then you may have to figure out a way to move it out of the way... or it could just be that the iris and pupil don't have a color set...