1. Preheat oven to 350 degrees.
2. In a medium bowl, stir together the pumpkin, brown sugar, eggs, and oil. Mix well.
3. In a large bowl, mix the flour, oats, cinnamon, baking powder, and baking soda.
4. Add the pumpkin mix to the flour mix. Stir well.
5. Grease a 9" x 13" baking pan with butter or margarine.
6. Pour the batter into the greased baking pan.
7. Bake for 30 minutes.