A statement this week from Reporters Without Borders will make unsettling reading for foreign companies eager to join China's internet boom. The press freedom watchdog accused the US internet portal Yahoo of helping Chinese authorities to identify and convict a local journalist of leaking state secrets.

In April, Shi Tao was sentenced to 10 years in prison for sending foreigners an e-mail that Chinese authorities alleged contained state secrets. Reporters Without Borders said Yahoo's Hong Kong subsidiary had supplied the Chinese "investigating organs" with "account information" that helped them to track the journalist down.