Johannesburg - South Africans showered praise and affection on the country's favourite son Friday as former president Nelson Mandela celebrated his 90th birthday amid appeals for a renewed commitment to his legacy of forgiveness and reconciliation. 

Mandela's predecessor as president, F W de Klerk, who was jointly awarded the Nobel Peace Prize with Mandela in 1993 for his work with the anti-apartheid icon towards ending white minority rule, called him one of the greatest figures of the past century and a "born leader." 

"All of us as South Africans glow in the light of fame in part because we stand on the shoulders of this (Mandela) and other giants," said his successor, President Thabo Mbeki, whose leadership style has at times drawn unfavourable comparisons with that of Mandela. 

Radio stations were flooded with messages of goodwill towards the man who came to embody the struggle for a democratic South Africa during his 27 years in prison, with only a few voices criticizing the outpouring of sentimentality. 

As rock group Simple Minds' 1988 song "Mandela Day" rang out across the airwaves, many wanted to share their memories of meeting the man credited with a Midas touch for steering South Africa through the transition to democracy without major bloodshed. 

Prisoners were also marking the festivities at a ceremony at the Drakenstein Correctional Centre, formerly Victor Verster Prison, from which Mandela emerged a free man on February 11, 1990. 

But the occasion also gave rise to expressions of concerns about the perceived erosion of Mandela's legacy of reconciliation and forgiveness. 

As Business Day newspaper noted in an editorial referring to recent remarks from a youth leader of Mandela's African National Congress exhorting violence in support of ANC president Jacob Zuma, Mandela's "long walk" to freedom had, in his own words, "not yet ended." 

Mandela's longtime friend, advocate George Bizos, who represented him during his 1964 sabotage trial, said Mandela was "very disappointed" at some recent events in South Africa but was optimistic everything would turn out well. 

At a birthday dinner in London last month, Mandela expressed concern over the two weeks of xenophobic bloodletting in South Africa in May, in which over 60 African migrants were killed. 

Mandela has chosen to celebrate his birthday with a private party for friends and family at his ancestral home in Qunu, Eastern Cape province. 

Despite the private nature of the event, his compound was swamped by television crews Friday ahead of the arrival of an expected 500 or so guests for Saturday's party. 

Invitees will likely also be called on to raise a glass to Mandela and former Mozambican first lady, Graca Machel, who celebrate their 10th wedding anniversary on Friday. (dpa)