BBC correspondent in Islamabad
A long-awaited bill on women's rights has been presented before Pakistan's National Assembly.
Many MPs feel women in rape cases have little legal protection
It has split MPs in the opposition and government parties and has even divided president from prime minister.
It seeks to abolish laws discriminating against women, including the Islamic Hudood ordinance, which opponents say fails to separate rape from adultery.
Conservatives say MPs should not abolish laws that were made in the name of Islam.
The bill was presented by an opposition MP from the Pakistan People's Party (PPP), Sherry Rehman.
But as soon as it was tabled, several members from a party allied to the PPP, the PML (N), got up to oppose the move.
The division within the ranks of the governing coalition was equally evident.
A number of women MPs said the existing laws were discriminatory, but other voices on the government benches criticised any move to abolish laws they said were made in the name of Islam.
The split goes right to the very top.
An official commission set up by the government recommended that the Hudood ordinance should be repealed and President Pervez Musharraf backs the move.
Musharraf (L) backs a new approach but Jamali differs
At a recent function on International Women's Day, President Musharraf said that in order to make Pakistan a moderate Islamic state there was a need to do away with all customs and laws that discriminated against women.
However, Prime Minister Zafarullah Jamali, and a large number of government MPs are opposed to the idea.
At the heart of the debate are two fundamental issues.
The first is the social custom whereby a woman who marries outside a tribe or clan is often killed by the family in the name of honour.
The other is the Hudood ordinance, which was introduced in the 1980s to enforce Islamic punishments but is regarded by many rights groups as discriminatory towards women.
The so-called honour killings are widely practised in rural parts of Sindh, Punjab and the North West Frontier Province, and in almost all cases the murderer is pardoned by family members under the controversial Islamic laws of Qisas and Diyat.
The Hudood ordinance is more contentious, as many Islamic groups and conservative MPs say its abolition would be an un-Islamic act.
Rights groups say it is a misinterpretation of Koranic injunctions as it fails to differentiate between adultery and rape.
According to Pakistan's independent human rights commission, in most cases of rape where a victim is unable to produce four male witnesses as required by law, she is charged with adultery.
The conservative alliance of six religious parties, the Muttahida Majlis-e-Amal (MMA), is vehemently opposed to abolition and is being backed by many PML (N) members.
However, supporters of abolition are trying to achieve some cross-party understanding.
A woman MP from the governing party, Kashmala Tariq, says if such a move succeeds, they would have enough support to pass a new law that gives equal rights to women.