Place the mascarpone, cream and sugar in a bowl and whisk until soft peaks form. Set aside. Lightly grease and line a 7cm x 32cm tin with non-stick baking paper with enough paper to hang over the sides. Dip 6 sponge fingers in wine and place in the base of the tin. Top with half the strawberries and half the raspberries. Spread with half the mascarpone mixture. Dip another 6 sponge fingers in wine, place on top of the mascarpone and top with remaining berries. Top with remaining mascarpone mixture.
Dip the remaining sponge fingers in wine and place on top of the mascarpone. Cover with plastic wrap, place on a baking tray and weigh down with cans of food. Refrigerate for 8 hours or overnight. Turn out onto a serving plate. Place the extra cream and sugar in a bowl and whisk until soft peaks form. Spoon over the trifle to serve. Serves 8.