Sorry - should have been clearer in my explanation: I'm creating a character by dialling the standard V4 and using the standard morph packages, so no geometry other than what's already there is being used.

I've just re-created the figure in a slightly different order (applying the texture then running the EZSkin script before dialling the changes and adding hair) and this time there is no problem.

Is there something about the order in which you do things that makes a difference here?