According to the skunk guy on a PBS show, if I remember right, you can use a mixture of hydrogen peroxide, baking soda and a touch of mild detergent.

Looks like my memory isn't shot yet, how the hell did that happen?

Searching the web turned up:
- 1 quart of hydrogen peroxide 2%
- 1/2 cup baking soda
- 2 teaspoons liquid soap (Dawn dish-washing soap works best)

From:
http://www.wisegeek.com/how-can-i-remove-skunk-odor-from-a-dog.htm

I have never used it but the skunk guy was shown mixing it up and using it on his dog.