Preheat oven to 325°F.

In a food processor fitted with a steel blade, process the cookies until they are small crumbs and add the sugar. Slowly pour in the melted butter, and blend until crumbs are moistened. Press the mixture into the bottom of a 10-inch springform pan and press with your hand to evenly cover the bottom. Bake for 10 minutes. Remove from the oven and cool while you prepare the filling.

In the large bowl of an electric mixer fitted with the paddle attachment, beat the cream cheese and sugar until blended and smooth. Unless the cream cheese is really soft, this may involve using a rubber spatula to press it out of the center. While the mixer is running, beat in the eggs one at a time. Add the pumpkin, cream, vanilla, and rum.

Pour the cream cheese filling into the crust. Place the cake on the middle rack, and bake for 1 hour and 45 minutes. Remove it from the oven and let it cool for 15 minutes in the pan, on a wire rack.

Turn the oven up to 450°F.

Whisk together the sour cream, sugar, vanilla and spices in a small bowl. Spread the sour cream topping evenly over the top and return cheesecake to the oven for another 10 minutes. Remove from the oven, and again cook on the wire rack for 30 minutes or an hour, then refrigerate for several hours, or overnight, to completely chill.

When ready to serve, run a sharp knife between the cake and the side of the pan before releasing the springform. Keep the cake on the bottom part of the spring form and place on a decorative cake plate.