Preheat oven to 350 degrees F (175 degrees C). Grease a 9×13 inch baking pan.
In a medium bowl, mix together the eggs, oil, sugar and pumpkin until smooth. Sift together the flour, cinnamon, cloves, ginger, nutmeg, baking soda, baking powder and salt. Stir into the pumpkin mixture.
Spread evenly into the prepared pan and bake for 25 to 30 minutes. The bars should spring back to the touch when done. Allow to cool before frosting.