He joined e-business software maker Vignette last April as vice president and general manager for Asia Pacific.
Ang began his career with IBM in 1969. He became managing director of IBM Singapore in September 1998 and grew the local office to become the region's headquarters.
He also served as IBM Global Services Asean/Southeast region general manager.
Coincidentally, Network Associates CEO George Samenuk is also an IBM veteran. Samenuk held several senior management positions with Big Blue over the course of 22 years, including a stint as president and general manager of IBM's Asean/South Asia.
The computer security software maker Monday announced the appointment of ex-E*Trade executive Stephen Richards as chief financial officer.
Network Associates' top three executives resigned at the end of last year, led by chief executive William Larson, whom Samenuk replaced on January 3.
Thereafter, the company said that a revision in its accounting practices would turn an expected operating profit into a net operating loss of US$130 million to US$140 million, or about US$0.41 a share. Previously, analysts had been forecasting a gain of US$0.31 a share for the quarter.
Network Associates comprises four business units: McAfee for anti-virus; PGP Security which provides firewall, intrusion detection and encryption; Sniffer Technologies for network and application management, and Magic Solutions, providing Web-based service desk solutions.
Nasdaq-listed Network Associates last traded at US$7.45, up US$0.25.