NEW YORK (Dow Jones)--The U.S. equities markets are mixed after rumors flew on the trading floor that General Motors may have some accounting concerns of its own. The Dow Jones Industrial Average is down and the Nasdaq is flat. General Motor's stock, which had been halted on the the New York Stock Exchange at 51.50, is now trading slightly higher at 51.95, down 1.13, or 2.2%. There has been no news from the company.