Mix pudding according to package directions. Once set lightly fold in cool whip. Place a layer of whole graham crackers in bottom of an 8x9 cake pan. Break crackers in pieces if need to to cover whole bottom, just don't crush. Pour 1/2 of the pudding mix on top of crackers. Place another layer of graham crackers and then the rest of pudding. Finish off with graham crackers. Put icing in microwave for 35 seconds to melt, stir and pour over last layer of crackers. Chill for 1 hour and serve.