Preheat oven to 350 degrees. Grease and flour a jellyroll pan (large cookie sheet with sides). In a mixing bowl, beat eggs on high for five minutes. Gradually add white sugar, pumpkin, and lemon juice. Add flour, cinnamon, salt, baking powder, and ginger. Spread batter evenly in pan. Sprinkle pecans evenly on top, and press lightly into batter and then bake for 12 to 15 minutes, or until it springs back when touched. Loosen edges with a knife. Turn out on two dishtowels that have been sprinkled with powdered sugar. Roll up cake, and let cool for about 20 minutes. To Make Filling: Mix confectioners' sugar, vanilla, butter or margarine, and cream cheese together till smooth. Unroll pumpkin cake when cool, and spread with filling. Re-roll, and push aside the dishtowel. Unroll long sheet of waxed paper. Put pumpkin roll on waxed paper. Dust pumpkin roll with powdered sugar. Twist ends of waxed paper like a piece of candy. Put pumpkin roll in refrigerator and chill overnight. Before slicing, dust with powdered sugar. Serve chilled.