In the top of a double boiler, beat 3 egg yolks and sugar until mixture is thick and pale in color. Soften gelatin in the 1/4 cup water and add to the egg mixture, stirring occasionally until the cream is smooth. Stir cream over cracked ice until it is cool and begins to set; fold in 3 egg whites stiffly beaten, heavy cream, whipped cream and dark rum. Turn the mixture into baked pie shell. Decorate with whipped cream, sprinkle with chocolate shavings.