California governor Arnold Schwarzenegger's plans to reduce all state employees pay to the minimum wage are being blocked because the payroll system is run on COBOL.

Schwarzenegger signed an executive order last week to cut the salary of the state's 200,000 employees to the minimum wage until the state budget, currently 36 days behind schedule, is passed.

But State Controller John Chiang told the Senate Committee on Governmental Organisation that this was impossible as the payroll system was written 30 years ago in COBOL and there weren't enough programmers to do the job.

Chiang estimated that with current resources it would take six months to make the change, and then nine to 10 months to reverse them.

"Pragmatically, we just can't get the system to work in a timely manner for us to implement payment of minimum wage," Chiang said, according to the Sacramento Bee.

He has said he will ignore the order and issue cheques as normal because of the issue.

"It's an example of a number of computer systems in which the state made a large investment decades ago and has been keeping it going the last few years with duct tape," said Michael Cohen, director of state administration with the Legislative Analyst's Office.

COBOL, or Common Business Oriented Language, was developed in 1959 and was hugely popular for use in legacy systems, particularly in military and government systems.

But concerns over the Year 2000 problem led to many such systems being replaced with more modern code and the supply of trained COBOL programmers has shrunk rapidly ever since.

"COBOL programmers are hard to come by these days," said Fred Forrer, the Sacramento-based chief executive of MGT of America, a public-sector consulting firm.

"It's certainly not a language that is taught. Oftentimes, you have to rely on retired annuitants to come back and help maintain the system until you're able to find a replacement."