JOHANNESBURG -- Mohale Mahanyele shed his banker's-gray suit jacket and merrily lowered himself on his haunches onto the plush carpet of his executive suite in a tony suburban office tower.

"You gather around in a circle, and everyone squats. Then you pass around the calabash, and everyone takes a drink," he said, demonstrating the traditional way to consume sorghum beer, a thick, sour-tasting beverage that African women have brewed in villages for centuries. "If you're standing up, it's a sign of disrespect."

Mahanyele is chairman and chief executive officer of National Sorghum Breweries, by far South Africa's most successful black-owned business. He was explaining how his company reversed the long-term decline in sales of the low-alcohol, high-protein drink after buying the business from a state-run monopoly in 1990.

"We understand the product much better," said Mahanyele, South Africa's foremost apostle of black economic empowerment. "We have a color fit and a culture fit with our customers."

Not many other corporations can make such a boast in South Africa, a country that is more than 75 percent black but is ruled by its white minority.

As the legal and political pillars of apartheid crumble, the economic barriers to black advancement have been slow to fall -- and nowhere more so than in corporate boardrooms and executives suites, which are nearly as white as ever.

Just 2.4 percent of the managers in South African corporations are black, a percentage that has been virtually unchanged for five years.

"To put it crudely, there's still a blacks-can't-hack-it mentality in corporate South Africa," said Linda Human, a researcher and consultant on human resource development.

"Progress has been extremely slow," agreed University of South Africa business professor Karl Hofmeyr. He just completed a survey of executives that found most accept the need for affirmative action. But about 40 percent had serious doubts about the ability of blacks to perform. "There's still a lot of prejudice out there," Hofmeyr said.

Some of the slow progress is the inevitable legacy of apartheid, which, among other things, left black education in shambles. More than half of all blacks are illiterate; fewer than 1 in 10 who starts school gets a high school diploma, and nearly 9 in 10 black teachers are underqualified. Moreover, the nation's four-year recession has thrown 500,000 people out of work -- hardly a climate in which to launch an aggressive black recruitment drive.

But part of the problem is that corporations have not been trying especially hard. South African businesses still spend just 1 percent of their payroll costs on training, well below the 5 percent-plus levels common in Asia and the West. As a result, South African workers were rated next to last in a recent productivity survey of 15 developing nations. And staggering racial gaps persist in certain professions. In a nation of 30 million blacks, South Africa has just 63 black chartered accountants and not a single black stockbroker.

Given all this, National Sorghum Breweries's record has been all the more remarkable.

When the government decided to privatize the sorghum beer industry in the late 1980s -- and hired Mahanyele, then a management consultant, to advise it -- one analyst said it was unloading "an old Third World product doomed to die." Sales had been dropping for 20 years, as blacks migrated to cites from villages where the drink is embedded in rural culture.

"There were a lot of leaders in the black community who thought we were being set up to fail," said Mahanyele, 54.

In addition to the adverse demographics, the breweries had to overcome sorghum beer's political stigma, created during the 80 years when the white-minority government was in the brewing business. "Kaffir beer," as it was known, became a symbol of white oppression, just as government-run beer halls in black townships became a target of boycotts and burnings.

"Here was a drink that had always been associated with festive occasions, and it had been taken away from us and tainted," said Mahanyele. "It was humiliating, degrading. I wanted to restore the dignity of sorghum."

Mahanyele had to raise $20 million to purchase the business and its 21 factories nationwide, but he had no access to white capital. So he did something never attempted here: He sold shares to blacks, building on the centuries-old custom of stokvels -- small, informal savings societies -- in black communities.

National Sorghum Breweries has 10,000 shareholders, more than 90 percent of whom are black -- a novel arrangement in a country where few blacks own the roof over their heads. Its board and management team, once all white, is now nearly all black. Most of its contractors are black, including 500,000 small, independent distributors. It employs a quarter of all South Africa's black accountants, and is putting more than 100 of its executives through an MBA program that it runs on the premises.

The change did not come without friction. Mahanyele got into a bruising fight with some of the white executives he fired, eventually taking out full-page newspaper ads to defend himself against charges of racism. "I had some of the old board members tell me to my face they couldn't work for a kaffir chairman," he said. "It was a very traumatic time, a real power struggle."

But National Sorghum Breweries has nearly doubled its volume in the past three years, while it has paid 20 percent or better annual dividends. It is beginning to diversify into other products -- food, soft drinks, computers and, most daunting of all, conventional beer, a market in which the giant South African Breweries has a 98 percent share.

The National Sorghum Breweries success, however, has been a one-of-a-kind phenomenon here, and Mahanyele argues that the black-led government expected to come to power next year after the country's first all-races election will have to enact affirmative-action legislation to break down barriers to broader economic advancement by blacks.

"The business community did a commendable job of putting pressure on government to end apartheid, but when it comes to putting pressure on itself, it hasn't even scratched the surface," he said. "They'll pay for scholarships a lot faster than they'll hire people. And when they do hire, it's often tokenism. You tend to get blacks in areas like public relations. Or you get companies scrambling to put blacks on their boards, but in nonexecutive positions."

For 45 years, the South African government has legislated what is probably the most effective affirmative-action program anywhere in the world -- for whites. Under apartheid, a vast array of job categories in the private sector was reserved for whites.

Now, the South African Chamber of Business says that two wrongs don't make a right, and it has vowed to fight affirmative-action laws. The chamber recently released an affirmative-action proposal that called for a voluntary industry standards on the education, training, recruitment and advancement of blacks, but it warned of the "market distortions" caused by legislated quotas.

The African National Congress, which is expected to lead the next government, has left its options open regarding such laws.

There is some evidence that negative stereotypes are weakening, although there is plainly a lot of ground to cover on that front. Many white managers still see black workers as lazy, unmotivated, prone to drunkenness. Some argue that the African belief in ubuntu -- the proposition that a person achieves humanity through other people -- does not mesh well with the cutthroat culture of capitalism.

"That's nonsense," said Mahanyele, pointing to the sharp growth of an informal economy, with its proliferation of black street hawkers, taxi drivers and shop owners who have taken advantage of the political liberalization of the past decade to start miniature businesses. This thriving sector will probably never amount to more than 5 to 10 percent of South Africa's gross domestic product, but it does help explain why, in a society with an official unemployment rate of more than 40 percent and no governmental safety net, few people actually starve.

Blacks account for well over half of the consumer market in South Africa, and the companies with the best record of moving blacks into executive positions are those that feel market pressure from their customers. One such company is South African Breweries, which sells 80 percent of its beer to blacks and has nearly one black manager in 10. It is bracing for a challenge from National Sorghum Breweries, which has gone into partnership with a German firm and expects to have its first conventional -- or "clear" -- beer brewery operating by November.

"I think we need 100 NSBs," said Jabu Mabuza, ex-head of the Federation of African Business and Chambers of Commerce, who has just been hired by South African Breweries to help fend off Mahanyele's challenge. "And if there is going to be a competition, it will be very good for black empowerment."