If you are already aware of this, that's great. If not please do NOT feed your dog raisins or grapes. It causes acute renal failure in some cases. This is not a myth or urban legend, it is fact. It has been verified. I only heard of this today, but luckily I have never given my dog grapes or raisins.
http://www.dogbreedinfo.com/grapeandraisin.htm
http://en.wikipedia.org/wiki/Grape_a...xicity_in_dogs
( I normally don't use wikipedia as reference, but this instance proves factual)
http://www.natural-dog-health-remedi...y-in-dogs.html
Please try to pass the word along to fellow dog owners, I don't see a reason why a couple grapes would be harmful and the articles seem to stand up to this as well, but why take a chance. There's other treats a dog can have that don't have the same adverse potential that grapes and raisins do.
Go pet your dog. You know you want to.