Cook package of lasagna; rinse & drain.
Arrange noodles flat on oiled surface.
Combine dressing mix with cream cheese.
Mix half of this mixture with the spinach; and spread 2 tablespoons of the spinach mixture over each noodle.
From narrow end, roll up each noodle and place seam side down in 9 x 13-inch baking dish.
Whisk tomato sauce and milk into remaining cream cheese mixture. When smooth, pour sauce over roll-ups.
Cover with foil and bake at 325°F. for 25 minutes.
Sprinkle with mozzarella, cover loosely and bake 10 minutes longer, or until hot & bubbly.