uv mapping on other side of mesh

How does one uv map a mesh on it’s opposite face(s), i.e. I can map a bitmap to the outside of an egg shell, but not the inside…?

a single face can only have 1 (one) image assigned and one set of uv coordinates

it is however possible to make faces render from only one side with material hacks. A similar technique could be used to make the texture [if applied as an image texture mapped using UV coordinates [as in not by pressing the texface button] visible on only one side]

I don’t however know where I uploaded my example .blend… I used a colorband on a sphere blend mapped based on normals [and you need to turn on “No V.Normal flip” in the edit buttons]

It found it’s way into the manual…
http://mediawiki.blender.org/index.php/Manual/PartIV/Map_Input#Single_sided_faces_.28Backface_Culling.29