Make the graham cracker crust: In a food processor or blender, process the graham crackers on high speed until they are finely ground. Add the margarine and pulse until the mixture resembles coarse crumbs. Pat the mixture into a thick layer in the bottom of an 8-inch springform pan, or thinner layers in 2 (9-inch) pie plates.
Make the filling: Have all the ingredients at room temperature. Preheat the oven to 325 degrees. In a food processor or blender, puree the tofu and pumpkin until smooth. Add the sugar, spices, soy cream cheese, and vanilla and process until smooth. Scrape down the sides as necessary.
Pour the tofu mixture into the prepared pie crusts and bake for 50 minutes, until the cheesecake mixture is firm.
Turn the oven off, leaving the cake in the oven for 1 hour. Remove and cool to room temperature. Refrigerate the cheesecake overnight. Serve slightly chilled.
Recipe Courtesy Patricia Greenberg