1.Make butterscotch filling. Combine ingredients in small saucepan, stir over heat until smooth; simmer, uncovered, about 10 minutes or until mixture thickens. Cool.
2.Preheat oven to 180°C/160°C fan-forced. Grease 25cm x 30cm Swiss roll pan; line base with baking paper, extending paper 5cm over long sides. Place a piece of baking paper cut the same size as Swiss roll pan on bench; sprinkle evenly with white sugar.
3.Combine dates, the water and soda in bowl of food processor, cover with lid; stand 5 minutes. Add butter and brown sugar; process until almost smooth. Add eggs and flour; pulse until combined.
4.Pour mixture into pan; bake about 15 minutes. Turn cake onto sugared paper, peel baking paper away; cut away crisp edges from all sides of cake.
5.Gently roll cake loosely, with the paper, from a long side; hold for 30 seconds, then unroll. Cover flat cake with tea towel; cool.
6.Make filling by sprinkling gelatine over the water in small heatproof jug; stand jug in small saucepan of simmering water. Stir until gelatine dissolves. Cool 5 minutes.
7.Beat cheese, cream and sugar in small bowl with electric mixer until smooth. Stir in gelatine mixture.
8.Spread cake with filling; dollop with butterscotch filling. Roll cake, by lifting paper and using it as a guide to roll.
9.Wrap roll in baking paper, then foil; place on tray. Refrigerate overnight before cutting.