Crumble or mash the feta cheese with a fork. Add the grated cheese, parsley, eggs and pepper.
Cut pastry sheets in strips about 2x12 inches. Stack them one on top of the other to prevent from drying. Brush each strip with melted butter, put one teaspoon of the filling on one end of a strip and fold over one corner to make a triangle. Continue folding pastry strip from side to side in the shape of a triangle until the entire pastry strip covers the filling. Proceed in this manner with pastry strips and filling until all are used. Put "tiropitakia" on a buttered baking sheet, brush with melted butter and bake in a moderate oven for 15 minutes or until golden brown. Serve hot. Makes about 4 dozen.