Preheat oven to 350 degrees. Grease a 9x13 inch pan. In a large bowl, combine pumpkin puree, eggs, brown sugar, white sugar and milk. Stir in cinnamon, ginger, cloves and salt. Pour into pan. Sprinkle dry cake mix evenly over the pumpkin filling. Sprinkle pecans over the cake mix. Drizzle melted butter over all. Bake in the preheated oven for 50-60 minutes, or until the edges are lightly browned. Allow to cool.