In a large bowl combine flour, baking powder, cinnamon, ginger, nutmeg and salt. In a medium bowl, beat eggs and brown sugar until fluffy, then beat in pumpkin, milk, molasses and melted butter. Stir the wet into dry until just moist. Do not overstir the waffle batter. Brush the iron with a little melted butter and cook 4 waffles, 4 sections each. Serve with toppings of choice.