When Thailand's parliament resumes sitting in March, there will be many weighty matters on the agenda, from corruption scandals to the terms of a controversial free-trade deal being negotiated with the United States. There is another issue, too, with consequences that could be as far-reaching as the trade talks. The Ministry of Social Development has drafted an amendment to Thailand's divorce law that would allow a wife to file for divorce against an adulterous husband. Adultery as grounds for divorce is found in civil codes around the world, since fidelity is held by many to be the bedrock of marriage. In Thailand, though, this rationale only cuts one way. If a wife sleeps with another man, her husband can seek an annulment. But the same is not true for a husband who has sex with a woman other than his wife. However, in a nod to the fondness for concubines among some Thai men, the law does allow women to sue for divorce if he supports a mistress, known as a mia. Some Thais trace this custom to the influx of Chinese migrants over the past century or two, who supposedly brought this tradition to Thailand - though I suspect it wasn't an entirely new idea. As it stands, the law is clearly designed to shield brothel-visiting husbands from the lawful wrath of their wives. As any visitor to Bangkok knows, there's no shortage of massage parlours, bathhouses and other euphemistically named establishments where sex is for sale. Not surprisingly, many women MPs are delighted that the government is trying to give wives the same rights as husbands in the civil courts. The big question is whether it will get the same enthusiastic backing from male MPs, who may be putting themselves in the firing line. The early signs are encouraging: the ruling party's chief whip has spoken publicly in favour of amending the law. Other male MPs have lent their support. They have probably figured out that opposing the proposal at this stage may generate unflattering headlines and possibly draw attention to their own marital affairs. Still, it will be interesting to see how they vote. One MP who knows more than most about male philandering is Chuwit Kamolvisit, an outspoken massage-parlour boss turned politician. He has warned that equality in the divorce court might create chaos in a society where prostitution is rife. 'Many men would be sued by their wives, and the courts would be overloaded,' he said. Mr Chuwit's real concerns may be focused less on the courts and more on his profits. An amended law might scare many men into being faithful to their wives, which could be bad for the massage business.