Preheat the oven to 350 degrees F. Grease and flour a 17 1/2- by 12 1/2-inch jellyroll pan.
With an electric mixer, beat the eggs, granulated sugar, pumpkin and lemon juice until smooth. Sift together the flour, ginger, salt, baking powder and cinnamon. Add the sifted ingredients to the egg mixture and blend until fully combined. Spread the batter in the jellyroll pan. Sprinkle the dough with the chopped pecans. Bake until a cake tester inserted in the center comes out clean, 14 minutes. Let the cake cool in the pan for 5 minutes.
Invert the cake onto a wire rack. Sprinkle some of the confectioner' sugar on a large tea towel and carefully transfer the warm cake to the towel, folding the sides of the towel over the cake. Roll the cake up in the towel and cool in the refrigerator thoroughly for about 45 minutes.
With an electric mixer, combine the confectioners' sugar, cream cheese, butter and vanilla and beat until smooth. Carefully unroll the cooled cake and spread the mixture on top of the cake. Gently re-roll the cake up and refrigerate it until you're ready to slice and serve. Dust with confectioners' sugar just before serving.