Preheat oven to 180 degrees C. Grease a 20x30cm baking pan.
In a small saucepan over medium heat combine sugar, 125g butter, water and dates. Cook, stirring frequently until dates have softened and the mixture is well blended. Remove from heat.
Combine the flour, bicarb soda and salt; stir into the date mixture then mix in the 1/4 cup orange juice, milk, eggs and 1 tablespoon orange zest. Spread the batter evenly into the prepared pan.
Bake for 15 to 20 minutes in the preheated oven until a toothpick inserted into the centre comes out clean. To make the icing combine the icing sugar, 85g butter, cream cheese and orange zest. Beat until smooth. Gradually mix in the remaining orange juice a tablespoon at a time until the icing is spreadable. Spread over the bars when cool. Cut into squares.