Palm, maker of the Treo smartphones, is expected to sell itself off this week, possibly as early as Thursday. The top bidders include two private equity firms, Texas Pacific Group and Silver Lake Partners, and two manufacturers, Nokia and Motorola. Palm is working with banking firm Morgan Stanley to close the deal, and is said to prefer selling to a private equity buyer. Nokia is considering bids in the $19 to $20 range, which is close to the $20 per share minimum that Palm is seeking. Motorola may enter the bidding process in an attempt to block Nokia from successfully acquiring the smartphone maker and thereby gaining some much-needed leverage in the U.S. market. Motorola’s struggling handset business could also use the boost represented by adding the Treo phones to its portfolio.