Melt butter in a large skillet over medium-high heat. Add onion and celery, and sauté 10 minutes or until tender. Add apple; sauté 3 minutes or until tender. Stir in sage, salt, and pepper.
Combine sautéed mixture, stuffing, raisins, and pecans in a large bowl. Add chicken broth and eggs; stir well. Spoon dressing into a lightly greased 13" x 9" baking dish. Bake, uncovered, at 325° for 50 to 60 minutes or until well browned.