Put digestive biscuits in a large resealable plastic bag, and crush them with a rolling pin until very fine crumbs form.

Pour crumbs into a medium bowl. Add butter, and stir until well combined.

Press the crumb mixture into a 22cm spring-form pan, spreading it 1 1/2 to 2 inches up the side; press flat. Chill crust in freezer at least 10 minutes.

Beat the cream cheese in a large bowl with an electric mixer at medium-high speed, until smooth. Beat in sugar gradually and beat in vanilla flavour. Fold in whipped cream.

Pour the filling into the crust; smooth the top with a rubber spatula. Starting in the center, arrange the strawberries in a circular pattern. Cover with plastic wrap, and refrigerate until firm, 2.5 to 3 hours.

Bring water to boil. Pour and stir crystal jelly mix gradually. Continue stirring for 5 minutes or until bubbles disappear then remove from heat. Set aside to cool but not harden.

Gently spoon the crystal jelly mixture over the cheese cake. Keep in refrigerator for 3 hours or until set before serving.