OVERLAND PARK, Kan. (AP) — Japan's Softbank says it has sweetened its offer for No. 3 cell carrier Sprint Nextel Corporation by $1.5 billion, raising it to $21.6 billion. The revised deal announced Monday also calls for Sprint shareholders to get more cash: $16.6 billion, up from $12.1 billion in the previous offer. Softbank will own about 78 percent of Sprint if the deal is completed, compared with a previous 70 percent. Satellite TV broadcaster Dish Network Corporation has launched a competing bid it values at $25.5 billion. But Sprint says a special committee of its board has determined Dish will not be able to come up with an offer superior to Softbank's. Sprint's second largest shareholder, Paulson and Company, says it will vote all its shares in favor of Softbank's sweetened offer.