Preheat oven to 350 degrees. Grease and flour a 10-inch Bundt pan.
Combine eggs, oil and vanilla; mix well.
Combine sugr, flour, cinnamon, baking soda, nutmeg, salt and baking powder. Add to the oil mixture, stirring to combine completely. Stir in grated zucchini; add raisins and walnuts to coat.
Pour batter into prepared pan. Bake 55 to 60 minutes, or until a toothpick inserted into the center of the cake comes out clean. Remove from oven and cool for 20 minutes before removing from pan.
For glaze, combine confectioners sugar, cream and vanilla; mix to a thin consistency; add more cream, if necessary. Drizzle over cooled cake. Serves 8.