Preheat oven to 350F. Grease a 9x13 inch baking pan, or a 10" bundt pan.
In a medium bowl, stir together cake mix, puddings, add the eggs, oil and water, mix well til blended. In another bowl, stir together the brown sugar, cinnamon, and nuts, Pour half of the of the batter into a pan, spread evenly. Sprinkle with half of the nut mixture. Cover with the rest of the batter, and sprinkle with the rest of the nut mixture.
Bake for 20 minutes in preheated oven, then turn the oven down to 325F and bake for an additional 35-40 minutes.