Stir the gelatin into 2 tablespoons of water, and set aside to soften. Put the sugar and wine in a saucepan, and heat to dissolve the sugar. Do not boil. Remove the wine from the heat and whisk in the gelatin until completely dissolved. Cool.
Arrange the grapes in 6 ramekins or tea cups. Pour over the wine mixture. Cover, and chill several hours to set. To serve, run a knife around the edge of the molds and dip the bottoms into hot water for a few seconds, then invert onto serving plates.
In a bowl, whip the heavy cream with the sugar and flavoring to serve alongside.