Security issuers will soon be able to sell and securitize excess servicing rights on Ginnie Mae interest- and principal-only strips, making loan pools less volatile while increasing the flow of capital back into the market. Ginnie officials unveiled the Excess Servicing Mortgage-Backed Security, or XMBS, program last week as a complement to its stripped MBS program, which was formally introduced just last month. Officials said the new XMBS program should be up and running by