Fear of physical danger to management and employees from a corporate extortionist, rather than possible chaos at stockholders' meetings, must have played a bigger role in driving corporate executives to engage in illegal payoff scandals, the reform-minded head of the Nomura Securities Co. said Oct. 17.But President Junichi Ujiie denied that he or his family have been threatened. "So far, no, because I quickly changed my telephone number," he said, drawing laughter from the audience.Speaking at the Foreign Correspondents' Club of Japan, Ujiie also detailed in English how the nation's top brokerage house is pressing ahead with internal reform to prevent further illicit dealing. Nomura executives, including former President Hideo Sakamaki, have been arrested in connection with the alleged channeling of money to a "sokaiya" corporate extortionist.The company has been under administrative penalties since Aug. 6. The penalties include a ban on stock-related trading on the firm's own account until Dec. 31.