Bring apricot nectar and butter to a boil in a large saucepan over medium heat, stirring occasionally. Remove from heat, and add white chocolate, stirring until melted. Gradually stir about one-fourth hot mixture into eggs; add to remaining hot mixture, stirring constantly. Stir in buttermilk and extracts.
Stir together flour and next 3 ingredients in a large bowl; add white chocolate mixture, stirring until blended. Pour batter evenly into 3 greased and floured 9-inch round cakepans.
Bake at 350° for 20 to 25 minutes or until a wooden pick inserted in center comes out clean. Cool in pans on wire racks 10 minutes; remove from pans, and cool completely on wire racks.
Spread White Chocolate-Cream Cheese Frosting between layers and on top and sides of cake. Spoon 1/2 cup raspberry jam on top of cake. Drizzle remaining jam down sides of cake. Store in refrigerator.
Note: For testing purposes only, we used Ghirardelli white chocolate.
Cake may be assembled and frozen up to 1 month. Thaw overnight in refrigerator; add raspberry jam just before serving.