Sleaze now threatens the new order in South Africa, and for Nelson Mandela the question is, once again, what's to be done about Winnie? Hugh Pope reports from Johannesburg
A huge cheer went up from the Soweto crowd as a regal figure appeared at Joe Slovo's funeral last month, swathed in a splendid African gown and flamboyant headgear. The applause was for a delighted and waving Winnie Mandela, darling of black South African radicals and now once again posing a great dilemma for her estranged husband, the President of South Africa.

The former "Mother of the Nation" and her radical comrades are still a popular and vital link between Nelson Mandela's ruling lite and the increasingly discontented people of the townships. If young, poor blacks are alienated, they may transfer allegiance from the government to the radical PAC (Pan Africanist Congress of Azania). On the other hand, the ANC is discovering that Winnie Mandela is the thorn in its side that every government suffers.

Mr Mandela's dilemma has been compounded by the demise of the veteran anti-apartheid campaigner Allan Boesak, accused of misusing nearly £400,000 of funds given by donors ranging from Scandinavian governments to Paul Simon's Graceland tour. Mr Boesak was forced to resign his appointment yesterday as South Africa's ambassador to the UN in Geneva.

A lawyers' report alleges no outsiders suspected anything when Mr Boesak used funds to pay for a luxury home, a holiday in Egypt, the reception after his second wedding and the debts of his second wife. The report indicated donated money also helped pay travel expenses of some ANC candidates in the run-up to last year's election.

Many a secret may lurk in the murky depths of a phenomenon known as "struggle accounting", by which organisations hid the true use of funds for fear of the apartheid-era government. A huge raft of non-governmental organisations, most of which do great and honest work, will no doubt come under new scrutiny after the Boesak affair, which only surfaced after an angry secretary spilled the beans to Scandinavian donor countries.

Many political commentators believe that, morally, it is a close call to move against Mr Boesak when others alleged to have played fast and loose with their positions remain in power; above all, Winnie Mandela, who tried to defuse Mr Mandela's wrath yesterday by making a statement to "clarify" the point that her recent criticisms of the government were not intended to be insulting or disloyal.

For the government, Mrs Mandela's status is a critical test of the revolution: her critics say she should be banished if the administration is not to be tainted, but her supporters believe that, despite everything, she embodies a passion for justice that the government cannot do without.

The latter opinion is going to be difficult to sustain if more allegations surface about Mrs Mandela. Yesterday, one of her critics accused her of failing to pass on to the ANC Women's League, which she heads, a donation of $140,000 from Pakistan's prime minister, Benazir Bhutto.

The allegation came from one of the 11 women who have resigned from the Women's League in protest at the behaviour of Mrs Mandela. Last week, the actor Omar Sharif arrived in South Africa to set up a tourism company with Mrs Mandela, as president of the ANC's Women's League. Their "Road to Freedom" tour will arrange visits to all shrines of the anti-apartheid struggle, and will split profits evenly between Mr Sharif and the league. The only trouble was that few other people in the league's 25-person executive committee had been informed, least of all the treasurer, Adelaide Tambo, widow of Oliver Tambo, the late leader of the ANC in exile. The 11 who resigned spoke obliquely in their joint statements but left little doubt that their objection was to the behaviour of Mrs Mandela.

Her daughter Zindzi also remains in the picture. She has set up a public relations company that Mrs Mandela has been promoting from her ministerial office - she has even accused the Rolling Stones of racism for choosing an experienced white rival as their representative for their upcoming Voodoo Lounge tour.

According to Allister Sparks, respected author of Tomorrow is Another Country, a study of South Africa's dramatic change in the past five years, sleaze does not yet run deep inside one of the world's more remarkable and united former liberation movements. "But it's a Catch-22," he said. "As long as corruption goes undisciplined, as long as there is a failure to stamp it out at the beginning, it rubs off on the government."

He believes Winnie Mandela is performing a critical political role. "She can do some pretty wild and irresponsible things. She articulates a radical element in the black population; she's bold, outspoken and a pugilistic personality. This is very important for the ANC. It keeps those people in the fold."

Winnie Mandela, 59, has survived worse political crises before. The sixth of 11 children of a school head turned businessman, she came from a relatively well-off family but soon turned to radical politics. Her given name, Nomzamo, means one who strives or undergoes trials.

Nobody doubts her charisma, least of all Nelson Mandela, who writes lovingly about her in his book Long Walk to Freedom. "I cannot say if there is such a thing as love at first sight, but I do know that the moment I first glimpsed Winnie Nomzamo, I knew that I wanted to have her as my wife," he wrote. "Her spirit, her passion, her youth, her courage, her wilfulness - I felt all of these things the moment I first saw her."

He realised her wish for a defiant career in politics would bring trouble, but, initially, she complemented his role. She was one of the only people willing to speak out for the ANC during the 1970s and 1980s, bravely enduring banishment, constant police harassment and 17 years of "banning orders" barring her from free movement and gagging her speeches. She was even jailed for 16 months, mostly in solitary confinement. She reacted with increasing radicalism.

"The time for speeches and debate has come to an end," she told a crowd in 1986. "We work in the white man's kitchen. We bring up the white man's children. We could have killed them at any time we wanted to. Together, hand in hand, with our sticks and our matches, with our necklaces, we shall liberate this country."

That year, she made her great mistake. She gathered around her in her small brick house in Soweto a group of bodyguards who became notorious as the Mandela Football Club, which acted as enforcers of rough justice from a kangaroo court operated by Mrs Mandela and Zindzi. Beatings were a frequent punishments for alleged crimes and informing to the police, but murders occurred - the killing of the 14-year-old activist Stompie Moeketsi Seipei in 1989 was only the most notorious.

Mrs Mandela was sentenced to six years' imprisonment for her role in the kidnapping of Stompie, although that was reduced to a £9,000 fine on appeal. Statements given at the time, however, repeatedly implicated her and Zindzi in actual assaults.

Initially, Nelson Mandela loyally stood by his wife in court. But in 1992, at a time when reports were circulating about an extra-marital affair, he made the break. The two are now separated.

"I am convinced my wife's life was more difficult than mine while I was in prison; my own return was more difficult for her than it was for me. She married a man who soon left her; that man became a myth. The myth returned home and proved to be just a man after all," he said at the time.

In the aftermath of the Stompie affair, Mrs Mandela was forced to resign all posts in the ANC and the Women's League. But she was far from finished. In December 1993, she was elected to the league's presidency. After the all-race elections of April 1994, she managed to use that power base to win the post of Deputy Minister of Arts, Culture, Science and Technology.

Her rise was not, however, the result of any residual love the President might have felt for his former wife. One of those close to Mr Mandela said he felt "total, total alienation". But the political reality is that she is powerful among the radicals, seen as more dangerous on the outside than on the inside.

That is what has protected her from government action, despite the fact that the Winnie Mandela scandals roll on. She has a luxurious Soweto home and there is another in Cape Town, "loaned" to her by her friend Hazel Crane, who has been convicted of illegal diamond buying.

More scandals are likely to surface from closer inspection of resistance activities in the dark days of apartheid, when wide-eyed and believing Europeans would give money to anybody who espoused the struggle for democracy in South Africa.

But this may all prove part of the learning curve for the ANC, whose great strength has always been openness, according to Allister Sparks. "It's egalitarian. There has never been any hesitation about criticising anybody. Remember - it's the only liberation organisation never to have split in exile," he said. "It'll survive this. And Winnie will continue to be important."