Preheat oven to 350°. In a large bowl, cream butter and sugar until light and fluffy. Add eggs, one at a time, beating well after each addition. Add pumpkin. Combine flour, pie spice, baking powder, cinnamon, salt, baking soda and ginger; add to creamed mixture alternately with buttermilk, beating well after each addition., Fill 24 paper-lined muffin cups three-fourths full. Bake 20-25 minutes or until a toothpick inserted in the center comes out clean. Cool 10 minutes before removing from pans to wire racks to cool completely., For frosting, in a large bowl, beat cream cheese and butter until fluffy. Add confectioners’ sugar, vanilla and cinnamon; beat until smooth. Frost cupcakes. Refrigerate leftovers.