Preheat oven to 350 degrees. Spray a 17-1/2 x 12-1/2 inch jelly roll pan with cooking oil spray and line the bottom with parchment paper. (Jellyroll pan sizes may vary.)
In a mixing bowl, beat together eggs, granulated sugar, pumpkin and lemon juice until smooth.
In a separate bowl sift together flour, baking powder, salt, cinnamon and ginger. Add to pumpkin mixture, stir until well combined. Spread the batter evenly into prepared pan. Sprinkle with finely chopped nuts, if desired.
Bake 13 to 15 minutes, or until a wooden tooth pick inserted in the middle comes out clean. Remove from oven and allow to cool in the pan for 5 minutes.
Loosen and turn cake onto a large tea towel (not terry cloth) dusted with confectioners' sugar. Carefully peel off parchment paper. Roll up cake and towel together. Cool in the refrigerator for 1 hour.
Prepare the filling by beating together 1 cup confectioners' sugar, cream cheese, butter, and vanilla until smooth.
When cake is completely cooled, unroll and spread with cream cheese filling. Roll up again without the towel. Wrap the pumpkin roll in plastic wrap and refrigerate until ready to serve. Dust with confectioners' sugar before slicing and serving.