Toss the chopped scallions in a bowl with 1 tablespoon olive oil, the chopped dill, salt and pepper. Remove 8 sheets of filo from the package. Reseal package and refrigerate it. Cover the filo you are using with a damp dish towel, well wrung out, and try to work hastily, as the pastry sheet have a tendency to dry out. Lay out one sheet of filo and brush thoroughly with olive oil. Lay a second sheet over the first, and brush again with olive oil. Leaving a margin of 1 inch down one short side of the filo, sprinkle one-fourth of the scallion mixture in a strip. Roll up from the same side, to make a long tube, packing the ends well. Place on a greased baking sheet. Repeat this procedure three more times. Cut each tube diagonally into four sections, brush with olive oil, and sprinkle the tops with sesame seeds. Bake in an oven preheated to 350 F until the tops are crisp and golden brown about 30 minutes. They are good hot or cold.