"A software problem is causing some Toyota Prius gas-electric hybrid cars to stall or shut down while driving at highway speeds, according to a published report.

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The newspaper quotes an official from Toyota as saying the stalling problem is due to a software glitch in its sophisticated computer system.

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Toyota spokesman Sam Butto told the newspaper the auto manufacturer identified a 'programming error' in the computer systems of 23,900 Prius cars last year and sent owners a service notice advising them to bring the cars into dealers for an hour-long software upgrade."

Prius hybrids dogged by software. (May 16, 2005). Retrieved on May 23, 2005 from here (CNN).