Stir together flour, baking powder, and salt; mix well.
In a large mixer bowl beat butter on medium speed of electric mixer for 30 seconds.
Gradually add sugar, beating till well combined.
Add eggs one at a time, beating 1 minute after each addition.
Beat in the 1 teaspoon vanilla and the orange peel.
Add flour mixture to egg mixture alternately with orange juice, beating well after each addition.
Fold in raisins and nuts.
Turn batter into two greased 7x3x2-inch loaf pans.
Bake in a 350° oven about 50 minutes or till wooden picks inserted near centers come out clean.
Cool loaves in pans for 10 minutes; remove from pans.
Cool completely.
Stir together powdered sugar, the 1/4 teaspoon vanilla,and enough milk (about 4 tea- spoons) to make of drizzling consistency.
Drizzle over cooled loaves; sprinkle with additional orange peel, if desired.