Combine all ingredients except cream in a stainless steel bowl. Over a double boiler, whisk mixture until thick and pale yellow, about 5 minutes. Put bowl over an ice bath and whisk until cold. Whip cream to soft peaks and mix thoroughly into sabayon. Refrigerate until ready to use.
To assemble: Slice sponge cake in half horizontally and cut into pieces just large enough to fit into a 2 1/2 quart clear bowl or trifle dish. Set aside.
Coat bottom of bowl with 4 tablespoons of pureed strawberries. Place a layer of cake in the bowl, filling in edges with scraps of cake. Mix rum, pineapple juice and coconut cream. Trickle 1/4 of mixture on cake. Spread 4 tablespoons each blackberry jam and strawberries onto cake. Top with 1/2 cup sabayon. Repeat layering process until bowl is full, ending with sabayon. Refrigerate several hours.
Topping Sauces: Peel, pit and/or seed the tropical fruit and raspberries. Puree in processor and sweeten with sugar to taste. Serve both sauces.
To serve: Scoop out sections of trifle and top with choice of or both sauces.
It's worth the work!
