Preheat oven to 350°F. Steep tea leaves in hot water 10 minutes. Strain. Add plum jam; mix well. Set aside. Dice 2 of the plums; halve remaining 4 plums. Mix diced plums, sausage, bread crumbs, onion, cinnamon and garlic powder in large bowl until well blended.
Cut each pork tenderloin lengthwise 3/4 of the way through. Open meat and flatten with meat mallet to 1/2-inch thickness. Spread 1/2 of the plum stuffing evenly on each pork tenderloin, leaving a 1/4-inch edge of meat. Roll pork tightly. Tie with kitchen string at 1-inch intervals. Place pork tenderloins in foil-lined shallow baking pan. Arrange halved plums around pork.
Roast 40 to 50 minutes or pork is until desired doneness. Brush with plum jam mixture during last 20 minutes of cooking. Let stand 5 minutes before slicing.