NEW YORK - A COMPUTER systems administrator was sentenced to 30 months in prison on Tuesday for trying to sabotage his company's servers out of fear he was about to lose his job, prosecutors said.

The US Attorney's Office in Newark, New Jersey, said Yung Hsun Lin received the longest ever federal prison term for a criminal attempt to damage a computer system.

He was also ordered to pay US$81,200 (S$117,090) in restitution to his former employer, pharmacy benefit manager Medco Health Solutions Inc.

Lin, 51, admitted he modified computer codes and added code to create a 'logic bomb' designed to wipe out servers on Medco's network in October 2003, around the time Medco was being spun off by Merck & Co, authorities said.

Lin feared he might be affected by resulting layoffs. Part of the code included script to launch the attack on his birthday, but it failed, they said.

Medco servers contained software applications relating to clients' clinical analyses, rebates, billing and managed care processing. The unauthorised coding was found by another computer administrator in January 2005, authorities said.