NEW YORK (Reuters) – David Einhorn, hedge fund manager and chairman of reinsurer Greenlight Capital Re Ltd, said Wednesday that the U.S. government's lawsuit against Standard & Poor's has made rating agencies vulnerable. Einhorn, who also runs the $8 billion hedge fund Greenlight Capital, said on an earnings call for his Cayman Islands-based reinsurer that the civil lawsuit reinforces short positions in Standard & Poor's parent McGraw-Hill and Moody's Corporation . “We believe the recent case against S&P is a negative for the rating agencies and Moody's is not immune,” Einhorn said. The U.S. …