Building a More Robust SSS Shader

Most beautiful explanation I've seen: http://www.lamrug.org/resources/skintips.html

I can't seem to get the specular map working.
I've found several forum posts of people having this problem, but there's never any reply.

SSS_fast_skin -> mia_material x

(no specular)                                                                                                    (overall specular 0.1)

Got specular maps working by plugging them into the primary and secondary specular colors rather than the specular weights. Still not completely happy with it. The face especially looks rather plastic-y, but I believe that to be an issue with the bump map.

mia_material_x  magic (on the right, mia_skin, on the left, mia_skin feeding into material x)