I am with Chairman Bill on this one: flash photography is, in my humble opinion, either done right or a complete mess; and an integrated flash is probably the worst tool for this task. I would try to minimize the need for the flash, placing the subject facing the source of light; but that is most probably the complete opposite of what you had in mind. Or, you could try to join your enemy, forget the flash and try some silhouettes.
Just my two cents; that is a very difficult situation, and I wish I had a better answer...