By any number of indicators, the nation's housing market is in recovery. But that may be the last thing the Federal Housing Administration (FHA) wants to hear right now. Last Friday, the mortgage insurance agency, part of the U.S. Department of Housing and Urban Development, announced the results of an independent annual audit projecting that reserves of FHA's main fund, as of September 30, were $16.3 billion less than its obligations for the current operating year. The estimate, far more grim than what had been forecast only months earlier, has renewed debate in Washington and elsewhere as to the need for a special infusion of funds - i.e., a bailout. It would be the first in the agency's 75-plus years.