discard skin from watermelon; cut into 2cm cubes, removing seeds.
Combine melon and strawberries in large heatproof bowl. Combine rind,
juice, sherry, sugar and water in medium pan, stir over heat, without
boiling, until sugar dissolves. Bring to boil; simmer, uncovered, about
5 minutes or until thickened slightly.
syrup over fruit in bowl. Cover, refrigerate until cold.