When Da Wen said "I do" to Xiao Qiang at their wedding in a Beijing restaurant on Saturday it was a union aimed not only at the joining of two people in love but also a bid to strengthen the fight against AIDS.

The two men, knowing that gay marriage is not recognized under Chinese law, still wanted to declare their union in public as an example to other gay couples in China.

Although their marriage cannot be officially registered, the couple received a certificate, complete with pictures of both men and the seal of "China's Happy Marriage Committee," an organization that doesn't exist.

Xiao Dong, director of a Beijing AIDS prevention voluntary team, said such gay marriages would help people in the gay community prevent AIDS.

He said marriage could seal relationships and avoid rapid changes in sex partners.

Xiao said the lack of a law to regulate same-sex marriages in China made it difficult for gay couples to maintain their relationships.

People in gay communities would often have several sex partners due to the absence of law, thus dramatically increasing the risk of them getting AIDS, Xiao said.

"Each attempt to fight the spread of AIDS is worth trying, including getting married," Xiao said in an interview with Beijing Times.

The couple only invited their friends in the gay community in Beijing to the ceremony.

It seemed a pleasant and moving moment when the two men hugged each other at the wedding, promising they would love each other always, but behind the event lay a sad story.

Da Wen, a Beijing native, only came to the realization that he was homosexual three years ago after he had married and become a father.

Knowing he couldn't keep his secret forever, he confessed to his wife and asked for a divorce but she refused, not wishing her child to be the product of a broken home.

However, Da then met Xiao Qiang, from Henan Province, at a party and it was love at first sight.

Da's "second marriage" does not qualify as bigamy because Chinese law doesn't mention gay marriage.

There was at least one dissenting voice after the ceremony that criticized its aim of AIDS prevention.

Tony Zhen, director of Shanghai Leyi, an organization which provides help for sex workers, said: "It's hard to understand the relation linking marriage and AIDS prevention."

Zhen said gay people might still have other sex partners even after marriage, and if a spouse found out about a love affair, there was no marriage law to protect him.

Zhen said he had been in love with another man for more than 10 years, but would not consider marriage before more Chinese people learned to accept the gay community.