Dozens of world leaders attend the memorial for Nelson Mandela, as tens of thousands of South Africans gathered under a rainy sky in Johannesburg's Soccer City stadium.

U.N. Secretary General Ban Ki-moon used the weather as a metaphor to describe Mandela's Rainbow Nation:

(SOUNDBITE) (English) UNITED NATIONS SECRETARY-GENERAL, BAN KI-MOON, SAYING:

"In nature, a rainbow emerges from rain and the sun. It is that blending of the symbol of grief and gratitude that I feel today."

President Obama and Cuban President Raul Castro put aside their differences and shook hands, as Obama made his way to the podium.

(SOUNDBITE) (English) U.S. PRESIDENT BARACK OBAMA, SAYING:

"We will never see the likes of Nelson Mandela again… And while I will always fall short of Madiba's example, he makes me want to be a better man."

In contrast to Obama's roaring ovation, boos were heard as South African President Jacob Zuma took the stage.

Organizers tried to drown