Soften gelatin in cold water and set aside. Beat egg yolks at high speed in mixer until ribbons form. Gradually add the white sugar and beat until mixture thickens. Add pumpkin, milk, allspice, 1/2 teaspoon cinnamon, ginger and nutmeg. Beat well.

Pour pumpkin mixture into medium saucepan. Cook over medium heat stirring constantly for 5 minutes or until thickened. Remove from heat and add gelatin mixture. Blend together and refrigerate until chilled.

Combine 1/2 cup of the powdered sugar and the remaining 1/2 teaspoon of the cinnamon. Stir and set aside. Beat whipping cream and vanilla until doubled in size. Gradually add the powdered sugar and cinnamon mixture; beat until soft peaks form. Refrigerate.

Beat egg whites (room temperature) at high speed until foamy. Gradually add the rest of the divided powdered sugar a Tablespoon at a time-beating until stiff peaks form. Fold into chilled pumpkin mixture.

Spread half of the pumpkin mixture evenly into baked pie shell. Spoon half of whipped cream mixture over pumpkin layer. Repeat layers ending with whipped cream mixture and sealing to the edge of the pastry. Chill until set.