TOKYO — Fired engine plant worker Kouichirou Fukudome shouts slogans with dozens of protesters outside truck maker Isuzu's towering headquarters, all demanding they get their jobs back.

Once unheard of in Japan, such protests are becoming more common as thousands of "temporary" workers — who often had steady jobs for years under various contracts — get fired by major companies like Sony and Toyota just as the global economic slump makes it unlikely they'll find substitute work any time soon.

The layoffs are a new phenomenon in a nation long known for its tacit guarantee of lifetime employment. The mass firings are creating broader social problems such as homelessness, with an inadequate safety net to handle them, because temporary workers can be forced out of company dormitories. Some find refuge in 24-hour Internet cafes; others return to the rural towns they once left in search of employment.

Fukudome, 47, worked for seven years at Isuzu on successive short-term contracts. He is upset that non-production employees have replaced him on the assembly line, simply because they are permanent workers who cannot be easily fired.

"There are a lot of them who aren't doing anything," he said. "I wouldn't buy an Isuzu now. They're being made by amateurs."

His battle is an outgrowth of a major shift in the world's second-largest economy in employment practices, which emerged in the 1980s but only became widespread after the government formally legalized it in manufacturing in 2004.

Global competition has driven Japan to create this new class of contract workers. Many of them work full-time, but they are less-well paid, have fewer benefits and are widely looked down on by others.

And as the economy sours, they are being laid off. In recent months, Sony Corp. has announced 8,000 job cuts, Toyota Motor Corp. 3,000, Isuzu Motors Ltd. 1,400, Honda Motor Co. 3,100 — all so-called temporary workers — and the government predicts some 125,000 of these people will be jobless by March.

In recent years the number of people working on contracts or on a part-time basis, which includes a much broader group of employees, has grown to 17.8 million people, or about a third of Japan's work force.

The disparity in treatment between contract and regular employees threatens to divide Japanese society, widening the gap between the haves and have-nots.

In previous downturns, Japanese companies coped by holding down wages, freezing employment and cutting costs, but there were few outright layoffs.

A new twist to this recession is the plight of these temporary workers — known in Japanese as "haken" (referred by an agency) or "kikan-jugyouin" (contract worker). As more are laid off, Japan's unemployment rate of 4.4 percent — still low by Western standards — is likely to climb.

Kenichi Furuya, 23, who has gone from job to job, including noodle shops, real estate sales and discount chains since he was 18, believes contract workers are unfairly treated.

"It's unforgivable for a nation to have all these people who can't find jobs," he says.

The growing numbers of jobless "haken" workers have led to broader social problems like homelessness that critics say Japan is ill-equipped to handle.

Those who have been kicked out of company housing have sought shelter and free meals at soup kitchens. Others stay at 24-hour cafes featuring "manga" comic books or Internet access.

Earlier this month, tents were pitched at a Tokyo park called "Haken Village," offering New Year's rice cakes, job counseling and medical checkups for the homeless during the period when government offices were closed for the holidays. The village was moved for a few days to a government gymnasium and closed after government offices reopened Jan. 5.

For years, the temporary worker's problems weren't properly understood because the status was initially used for students and housewives, working part time, said Shigeru Wakita, a law professor at Ryukoku University.

"Now, people realize their working conditions are an important problem," he said.

More broadly, temporary workers have created a lower working class that has stratified Japanese society and widened the wealth gap. The monthly wage for full-fledged workers averages about 350,000 yen ($3,900), 40 percent better than temporary workers' 210,000 yen ($2,300). That disparity grows when figuring the lack of bonus pay, pension and other benefits.

Many temporary workers also suffer emotional hardships because they are often treated as inferior losers, says Ryoichi Miki, secretary-general of the All Japan Metal and Information Machinery Workers Union.

"The worst thing is that they are treated like they are things, not human beings," Miki said.

Typically, contract workers get stuck in their lower status because companies only rarely promote them to full-time.

"They are discriminated in the workplace," said Takashi Araki, law professor at the University of Tokyo.

Japan's corporate chieftains defend the use of temporary workers as an effective cost-saver. Without them, Japan runs the risk of losing even more jobs to China, India and elsewhere, proponents say.

"It is not easy in Japan to reduce full-time workers," Honda President Takeo Fukui told reporters recently. "But protecting employment isn't the only duty of a company. It has to maintain a sound business."

All Hajime Tozuka, 43, wants is to live with his wife and two sons, who are back in northern Japan while he works in the Tokyo area.

Recently, he finally got a full-time job as a taxi driver.

"I have to keep working, no matter what the job is," he said. "If you don't have a job, you don't have a life."