A US firm has given the mainland's oft-criticised anti-piracy efforts a rare pat on the back. Computer-hardware maker Cisco Systems helped put four men involved in a counterfeiting operation behind bars last week after giving information about the facilities that produced the fake goods to local authorities in Shenzhen, Dongguan and Guangzhou. This led to raids at 15 locations in those three cities and the arrest of about 20 people last October, said I-OnAsia, the private investigation company that did the probe for Cisco. Four men were sentenced to between one to 41/2 years in jail on August 24 by a Shenzhen court for producing and selling the counterfeit networking hardware. 'We are certainly very happy to work with the government and police in China,' said Karen Chu Ho-yan, spokeswoman for Cisco Systems in Hong Kong. 'I think they have been very professional.' Cisco Systems set up an internal brand-protection team and hired I-OnAsia a few years ago to track down syndicates that were producing fake Cisco goods, Ms Chu said. The US has singled out piracy as a key concern. In July, President George W. Bush said: 'It's very important for emerging economies to understand ... in order to be a fair trading partner, that you've got to honour somebody else's intellectual property.'