Try parenting the hair figure to the original figure and make sure you check use bends of the parents in the dialogue box.  This way the parented figure will follow the bends of the parent figure.

You may also have to use the scale dials to raise the hair texture above the skin texture.

If you open the skin texture and the hair texture in a graphics app, are the uv's the same?

If they are, you can try applying the hair to the skin texture as an overlay and saving the combined texture as a new texture.