"Don't be afraid of us -- we are all the same." With these simple words, pint-sized Nkosi stole the show at the annual international AIDS conference in Durban in 2000 and seared the conscience of television audiences.
In spite of his tender years, the 11-year-old, already ravaged by the disease that was to kill him the following year, was able to get his message across in a way that grabbed headlines around the world.
"You can't get AIDS if you touch, hug, kiss, hold hands with someone who is infected," he told a spellbound audience.
Nkosi was saluted by the great and the good, including the former president Nelson Mandela for whom he was "an icon of the struggle for life".
One of those watching was the award-winning ABC television journalist Jim Wooten, who was inspired to pen "We Are All The Same", the book of Nkosi's life.
American screenwriter Keir Pearson, who co-wrote the Oscar-nominated screenplay for Hotel Rwanda, has now adapted the book for the cinema.
"It's a very special story. It is about giving. It can be a very powerful film," said Pearson.
He was in Johannesburg visiting Nkosi's adoptive mother Gail Johnson, an infatigable campaigner for the rights of AIDS sufferers.
The film is to be shot in South Africa at a date still to be set. Casting has already begun however with Australian actress Naomi Watts.
Watts, the star of movies such as "King Kong" and "The Ring", who was nominated for an Oscar for her performance in the 2003 film "21 Grams", will play the part of Gail.
"Naomi is an amazingly talented actress who can play just about any role," Scott Nemes, one of the film's producers, told AFP from Los Angeles.
Nemes said that Nkosi's story "needs to be told as a movie in order to raise awareness of the epidemic of the disease in Africa."
"The issue of AIDS in Africa is very important for Naomi as she works with the UN on behalf of a number of AIDS organisations," he added.
Her real-life character jokes that Watts has her sympathy.
"Poor girl. She will have to do hours of make-up, talk with hands and smoke a lot!" she laughs.
Gail adopted Nkosi when he was just two years old from an AIDS care centre which had been forced to close down. Nkosi's mother was already too ill to look after him and died shortly afterwards.
Gail travelled the world with little Nkosi in a bid to combat discrimination and stigma associated with people with AIDS. She then set up a home for youngsters known as "Nkosi's Haven" which has kept his legacy alive.
"It's mind blowing. Never in my wildest dreams, I never thought about something like this happening. It's an amazing recognition and makes me realize that what's happened with Nkosi has been inspirational to people," she told AFP.
The outspoken and flamboyant Gail has managed to ruffle quite a few feathers along the way and has been accused in some quarters of milking the publicity as she travelled the globe.
She is aware that the film could stir things up again but insists that she is ready to face any flak directed at her.
"Some people are going to come out with criticism and racialism. Black media will probably start to do it again, saying 'Gail is still making money with Nkosi'. But this time I think I won't keep quiet."
The part of Nkosi has yet to be cast, but the producers are hoping that the vast majority of the actors will be South Africans.