The revision represents a drastic U-turn for President Kim, whose popularity ratings plunged during the month-long unrest. The latest version of the law has been denounced by trade-union leaders, but is likely to quell calls for further industrial action, at least for the time being.
The law was first passed by the ruling New Korea Party at the end of last year, in a secret dawn session of the National Assembly at which no opposition MPs were present.
Its stated aim was to improve the competitiveness of South Korean companies by allowing them greatly flexibility in laying off workers.
But the sneaky manner of the law's passage, and its apparent bias in favour of employers and against trade unions, provoked South Korea's largest strikes, involving some 1.2million workers, and costing $3.28bn (pounds 2bn) in lost output.
The new version allows firms to impose flexible working hours, and removes the obligation for them to pay striking workers. But the planned relaxation of the rules on lay-offs, which are impossible under present law, will be delayed for two years. Firms are no longer allowed to sub-contract production and bring in strike- breakers during disputes.
Immediate recognition on a national level is given to the Korean Confederation of Trade Unions, which led the strikes but which is technically illegal under existing legislation. Multiple unions will be allowed within companies in five years.
The National Congress for New Politics, Korea's biggest opposition party, won a further concession when it agreed to passage of the bill only on condition that the National Assembly also revises another unpopular law, which grants new powers to the internal security agency.
For President Kim, however, the damage is done - indeed, public anger over the labour law has since been eclipsed by a corruption scandal over excessive loans which were made to the bankrupt Hanbo Steel Corporation.
Several of his closest advisers have been arrested on bribery charges, and at the end of last month the President made a televised apology for the failures of his government.
A senior North Korean politician who fled into the South Korean embassy in Peking last month will soon be allowed to travel to the South, according to officials in Seoul.
An official of the South Korean foreign ministry said that the Chinese authorities had agreed to allow Hwang Jang Yop to defect.
More talks will determine whether he travels to Seoul directly, or via a third country.