Sony said on Wednesday that online software upgrades to its new video game console, the PlayStation 3, will fix glitches that make some older PlayStation and PlayStation 2 games not run properly on the PS3.

Kaz Hirai, president and chief executive of Sony Computer Entertainment America, told Reuters that more than 8,000 PS2 games will play on the PS3, and that so-called "firmware" upgrades will address problems found with about 200 games since sales of the PS3 started last week in Japan.

"We are aiming for perfect compatibility. Our goal is 100 percent compatibility," he said in an interview. "We are trying to get there as quickly as possible."

A Sony spokesman said the glitches in the 200 games in question were related mostly to audio problems and conflicts caused by the fact that the game controllers, held in users hands as they direct the action on the screen, differ from one PlayStation generation to the next. For example, buttons found on a PS One may not cause the same action on a PS3.

U.S. sales of the PS3 start on Friday, kicking off a holiday season battle between the $30 billion video game industry's leading game console makers -- Sony, Microsoft and Nintendo. Microsoft's Xbox 360 launched a year ago, and Nintendo's Wii comes out on Saturday.

A limited supply, delayed debut and drop in the number of games built exclusively for the PS3 could hamper Sony's effort to remain market leader during this crucial holiday season.

Hirai confirmed that Sony expects to have 1 million units available in the United States by the end of the year. A Sony spokesman said the company's goal was to have 400,000 units available on Friday, and 6 million shipped worldwide by the end of March.

By contract, Microsoft expects to have shipped 10 million Xbox 360s by December 31, while Nintendo is targeting 4 million units.

Hirai said that supply issues are typical at the launch of new products, and it will take time to see which console will have the biggest effect on the market.