Doubt has been cast over whether the PlayStation 3 will be fully backwards compatible, despite earlier claims that the next-generation console will play both PlayStation and PS2 games.
Speaking to the IDG News Service, Sony spokesperson Reiko Sakamoto said: "It's hard to say the PlayStation 3 will be 100 per cent backwards compatible."
"But as we said earlier this year, we aim to make it so as much as possible."
Sakamoto's comments came after Sony published a list of games which are not compatible with the new silver slimline PS2 console, due to go on sale in Japan next month. A total of 38 PSone and nine PS2 games were listed, including Tekken 5, Hitman: Contracts and Resident Evil.
"We believe multiple factors are responsible," Sakamoto told IDG, explaining that the new console has a different chipset which is not compatible with the way some software is programmed, resulting in glitches such as hangs and slow game saves.
The consoles had already gone into production by the time compatibility testing began, and since testing is not finished more games could yet be added to the list.
This is not the first time backwards compatibility issues have arisen for a next-generation console - there was also considerable confusion over whether the Xbox 360 would play Xbox titles. A list of compatible games is due to appear on the official Xbox website within the next week or two, according to recent by Xbox VP Peter Moore.