Blend together sage, rosemary, garlic, fennel seeds, salt, and pepper in a food processor until a thick paste forms. With motor running, add wine and oil and blend until combined well. If necessary, trim fat from top of pork, to leave a 1/8-inch thick layer of fat. Make 3 small incisions, each about 1-inch long and 1-inch deep, in each side of pork with a small sharp knife, and fill each with about 1 teaspoon herb paste. Spread remaining herb paste over pork, concentrating on boned side, and tie roast with kitchen string at 2-inch intervals.
Put pork, fat side up, in a roasting pan and roast in middle of oven 6 hours. Transfer roast to cutting board and let stand 15 minutes. Discard string and cut pork roast (with an electric knife if you have one) into thick slices.
You can make the herb paste 1 day ahead and chill it, covered