Fill each uncooked manicotti shell with 2 sausages. (If hard to fill, partially thaw sausages.) In greased baking pan, 12 x 8 x 2 inches, spread 1/2 jar sauce; arrange stuffed manicotti in sauce. If desired, slice remaining sausages and scatter around manicotti, or save to use another day. Pour remaining sauce and the water over manicotti. Top with cheese. Cover tightly and bake in preheated 350ºF. oven for 45 minutes. Uncover and bake 15 to 20 minutes longer or until manicotti are tender. Serves 4.