ZBrushCentral

Problem with individual polygons being flipped on my mesh when retopoligising

Hi, at the moment I am working on a skull and I initially modelled it from a zsphere whereby the skull and lower jaw were one mesh. Now, I have retopologised the mesh so the skull and lower jaw are separate. I did the retopology in maya. I import the new retopolised skull into zbrush and it appears fine. However when I try to create a projection from the original highpoly onto the new retopolised skull there seems to be 3 or 4 normals on the new skull that become flipped. However in maya all the normals appear correct. I know you cannot flip individual normals in zbrush but has anyone encountered a similar problem like this before and is there a solution for fixing individually flipped normals of a mesh in zbrush or is there nothing you can do about it?