In a medium bowl, mix together the flour, cinnamon, nutmeg, salt, and cloves. Set aside. In a large bowl, whisk together the persimmon pulp 1 1/2 teaspoon of the lemon juice, baking soda, sugar, chopped dates, vegetable oil, and egg. Fold the dry ingredients into the persimmon mixture, and stir until just combined. Pour into the prepared pan, and gently smooth the top with the back of a spoon. Bake about 25 minutes, until lightly browned.