From the May 9 WSJ article, "Mortgage Firms Cool to Principal-Cut Plan":
But mortgage companies may face pressure to use the program. "I want to put the servicers on notice," Rep. Barney Frank (D-Mass.), a co-sponsor of the bill, said at a hearing last month. "If we see a widespread refusal on the part of servicers to cooperate voluntarily in what we see as an important economic problem...they can expect much tougher regulation in the future."