Pumpkin-Eggnog Cheesecake

1/2 cup(s) walnuts Sugar

2 tablespoon(s) (1/4 stick) margarine or butter , melted

4 large eggs

1 can(s) (16 ounces) solid-pack pumpkin (not pumpkin-pie mix)

2 package(s) (8 ounces each) cream cheese , softened

1 teaspoon(s) ground cinnamon

1/2 teaspoon(s) ground allspice

1/2 teaspoon(s) ground ginger

1/8 teaspoon(s) ground cloves Ground nutmeg

1 cup(s) prepared eggnog

1 tablespoon(s) cornstarch Walnuts for garnish