Boil maple syrup in 2 litre pan for 10 minutes, stir constantly. Stir syrup into beaten eggs over boiling water in double boiler, and cook while stirring till very thick. (15 minutes) Cool. Fold in whipped cream. Pour into lightly oiled 1 liter mold and cover. freeze 6 hours. may be made a day ahead. to unmold, sit pan in warm water about 30 seconds. remove. dig spoon into center and "turn out" mousse. neaten with a knife. return to freezer a few minutes to re-harden.Slice into wedges and enjoy.