Combine dates, water and cornstarch in saucepan.
Cook and stir until very thick; remove from heat.
Melt margarine.
Place two phyllo leaves, side by side, on a lightly dampened, lightly bread-crumbed cloth.
Brush leaves lightly with melted margarine.
Lay a second leaf on top of each leaf.
Brush each layer lightly with melted margarine.
Repeat using all of the leaves.
Place date filling 2 in. (5 cm) in from long edges.
Fold long edges in over the filling.
Fold over the ends.
Roll up dough, jelly-roll fashion.
Score top into 10 pieces with a sharp knife or scissors and place on greased cookie sheet.
Bake at 350°F (175°C) for 25 minutes, or until lightly browned.