'One guy went out and caught up with an old flame from 19 years ago after signing up for one of the websites, and left his wife of 13 years,' says Toby Jones, who runs the Hong Kong online dating service wheresmydate.com.hk.

'A friend of mine in London joined Friends Reunited and she had some guy she hadn't seen since school contact her. She may have been naive, but he was married and she didn't think there was any harm in catching up, so she agreed to go to dinner with him when he was staying in a hotel nearby.

'It was really nice to see him and they got on really well, she told me. At the end of the meal, they settled up. He took off his wedding ring and said, 'Let's go back to my room'.'

Since its launch five years ago, Friends Reunited has established a 12 million-strong membership base in Britain. However, it's also been cited in a number of court cases, blamed for marital infidelities and named as a partial cause of the country's rising divorce rate.

One 42-year-old father of four was jailed for trying to kill his wife after discovering she was seeing an old boyfriend with whom she was reunited through the site. A 56-year-old man left his wife of 35 years to marry a childhood sweetheart he hadn't seen since he was 11.

A 45-year-old was arrested and charged with bigamy after boasting on the website that he was marrying his new 24-year-old girlfriend. In another case, a 24-year- old cocaine dealer was jailed for three years after telling school mates on the site: 'I'm doing very well. I'm selling a lot of Charlie and I've got three sports cars.'

Even messages posted on the website about old teachers can lead to trouble. Retired teacher Jim Murray, 68, took former pupil Jonathan Spencer to court over defamatory remarks he put on the website about him. Spencer was ordered to pay almost $17,500 in damages.

Since its launch in Hong Kong at the end of last year, Friends Reunited has managed to avoid scandal. Its website features the testimony of one elderly member who writes: 'I found an old school friend I haven't seen for almost 45 years. We spent a wonderful weekend together chatting about our past. We both missed each other when I left school. We keep in contact now and I never want to lose her again.'

The expansion to Hong Kong is part of a move to take the successful British model - which makes money by acting as an intermediary for messages between old school friends - to English-speaking centres around the world.

Sister sites have been set up in Ireland, Australia, New Zealand, South Africa, Malaysia and Singapore. Friends Reunited spokeswoman Carolynne Bull-Edwards says the site is doing well.

She says she's unable to give the number of Hong Kong members because the figures aren't broken down by the country or territory in which people join. 'Internationally, we're seeing more than 75,000 people join every week - enough to fill a football stadium,' she says. 'In Britain, alone, we have 11 million members.

'We're focused on English-speaking countries and we're trying to move into new areas to see if Friends Reunited will work in different countries. We thought of Hong Kong because it's such a hub of different nationalities and we thought it would be successful there.'

Among those who've been keen on the service in Hong Kong are elderly users - customers who Bull-Edwards called silver surfers. 'These people are using the internet for the first time and have been really enjoying the site,' she says. 'They're very active in organising reunions.'

As for the scandals surrounding the site, Bull-Edwards says that, with so many members it's inevitable that such things arise. But they're isolated cases and most of the stories have happy endings.

A close look at the Hong Kong site indicates that it's far from being the social phenomenon it's become in Britain, where scores of celebrities have their details on the site.

Although the Hong Kong site boasts of having more than 1,000 schools, universities and work places listed, many of the schools have no entries and some have only one pupil listed. Many message boards and photo albums are bare.

International schools whose former pupils are likely to be scattered across the world seem to have the biggest complement. King George V Secondary School in Kowloon, for instance, has 145 students listed. But other major schools such as the Hong Kong International School have only 10 former students listed.

Language may be a barrier for many Hongkongers, but Bull-Edwards says there are no plans to make the site bilingual. 'We don't have the expertise,' she says. 'It isn't something we'd rule out though.'

Language aside, there are cultural reasons Hongkongers are less likely to use a service such as Friends Reunited. According to Peta MacAuley of the Hong Kong Psychological Society, Asians are less likely to use the service because they 'would never lose contact in the first place'.

Jones agrees. 'Because Hong Kong is so small, everyone knows what their old school friends are doing. They see them all the time,' he says. 'That kind of thing really just doesn't work here.'

In any case, he says, many schools now have their own websites reuniting former pupils and providing a free and specific channel for people to look up their old classmates and teachers.

That might explain why one former Hong Kong pupil who has moved overseas has been waiting in vain for a response to her appeal on a message board to track down her former best friend. 'We used to call each other 'fat head' and 'big head',' she says fondly. 'Does anyone know where she is?'