If you work in Hong Kong showbiz long enough, eventually your unauthorised image gets used by some nightclub or dodgy company on the mainland. But it had to be a first when a Guangdong hospital used a Hong Kong movie star's photo to advertise its 60-yuan (HK$70) circumcision service. That was the fate of heart-throb Louis Koo Tin-lok, who was recently told about the unauthorised ad. An embarrassed Koo said his movie company was dealing with the matter. He said similar problems plagued many fellow actors and other famous folk in the broadcasting business. He had good reason to say that. Just this spring, for example, Zhao Yong, Guangdong's most popular TV broadcaster, found her photo used by Heaven on Earth, one of the largest nightclubs in Beijing, identifying her as its hottest hostess. One irreverent reporter asked Koo if he endorsed the sentiment behind the hospital's ad - that is, whether Koo was indeed circumcised and therefore a good exemplar of the hygienic practice. Koo declined to comment.