Doing what ND sadi in 2nd post. You could either use Sculptris, or even use a higher poly mesh in Maya and use the sclupt geometry tool to create the wrinkles manually. Or you can just move selected vertices or edge loops around a fair it like you would do for an organic model, so when you smooth it, it will have the wrinkles set for you. Try Sculptris, its free.
cheers bullet
bullet1968
"A Darkness at Sethanon", a book I aspire to model some of the charcters and scenes