In a separate bowl, mix together the milk, pumpkin, egg, oil and vinegar. Combine the flour, brown sugar, baking powder, baking soda, allspice, cinnamon, ginger and salt, stir into the pumpkin mixture just enough to combine. Heat a lightly oiled griddle or frying pan over medium high heat. Pour or scoop the batter onto the griddle, using approximately 1/4 cup for each pancake. Brown on both sides and serve hot.