@golf07 - This article also explains why they always say that dogs can't have chocolate. My dog really put this to the test though.
She was somehow able to reach some miniature candy bars that were left out on the coffee table. She devoured every one of them, wrappers and all.
She is a big dog, weighing around 75 pounds, and the vet said she would be OK. I had a friend who was not so lucky. She had a Yorkie who got in to some chocolate and ended up not making it.
He was very old and had some other problems, but I think the chocolate is what set him over the edge. The theobromine toxicity was too much for his little body to handle.