"I was expecting to be booed," he tells me the following afternoon, in a hotel on the Croisette, the boulevard edging the Cannes shoreline. "Then we got a 16-minute standing ovation, which was double the amount of time we got for Precious."
The reviews were less enthusiastic, to put it mildly. According to one critic, The Paperboy was "transcendentally awful". When I ask Daniels why he thinks there is such a disparity between his experience and the reactions of a sizeable section of the press (their screening ended in a mixture of cheers and jeers), he is surprised.
"I was so traumatised by two reviews I read of Shadowboxer," he says, referring to his debut feature about a terminally ill assassin (Helen Mirren) and her stepson-cum-lover (Cuba Gooding Jr), "that I made a point never to read a review again. Ever." In other words, this is the first time that he has heard there were other poor notices. "But I think that the people speak. Two thousand people standing on their feet for 16 minutes was not a figment of my imagination."
Personally, I enjoyed The Paperboy. It is bonkers and overheated, but this is part of its appeal. Adapted from Pete Dexter's 1995 novel by the author and Daniels, the film is a sweaty, sexy, violent, not entirely serious melodrama, in which Kidman, Matthew McConaughey, Zac Efron, John Cusack and singer Macy Gray throw themselves into against-type roles with conviction.
Column inches have been devoted to a scene in which Kidman's tragic floozy, Charlotte, urinates on pretty boy Efron. But this is just one of many gobsmacking moments in a film that is unashamedly lurid, moody and feral, with performances that bring a gallery of complicated, conflicted characters vividly to life.
"I'm not interested in being safe, and I'm willing to fail because of that," Kidman commented during Cannes. Even this, however, can't prepare one for the sheer audacity and daring of a scene in which the 45-year-old mother of two has what's being called "telepathic sex" with John Cusack's repulsive death-row inmate. The episode is weird and perversely erotic, and leaves you feeling somewhat grubby.
Some in Cannes put their necks on the line and suggested she might pick up an Oscar nomination for her performance, talk which now seems vindicated by her nods for Screen Actors Guild and Golden Globe best supporting actress awards.
"She is fearless and I have fallen in love with her," Daniels says. "I'm so in awe of working with her because she transformed." He made Kidman do her own make-up as a condition of playing the role and told her to gain weight, believing this would help the actress find the character. "I said, 'You have to put on some pounds,' " he explains with a laugh. "That was what was key to the discovery, because she had the jiggle but she didn't have the junk in her bunk."
So why wasn't The Paperboy getting more love from critics? Daniels, a black, gay, self-made man who grew up poor in a project in Philadelphia, made his name as the producer of the Oscar-winning Monster's Ball and daring pedophile character study The Woodsman, has a theory that goes back to Shadowboxer. He once told me he believed if that film had been made by an Italian or French filmmaker, American critics would have embraced it more. "But since I'm an African-American filmmaker," he said, "how dare I think out of the box like that?"
Hearing now about the critical reaction to The Paperboy in Cannes - a snobby environment, to be fair - he says: "What that means to me, again, is that as an African-American, I had better stick to telling African-American stories."
Prior to his involvement, Pedro Almodovar had been working on bringing Dexter's book to the screen as his first English-language film. When the Spaniard dropped out, Daniels stepped in. "So I think critics will take quite deep offence that I am not Pedro Almodovar telling this story."
At the end of the day, "I am judged differently as Obama is judged differently," he says. "It's just the same. He cannot be the man that Bush was and say, 'This is the way it has to be', because then he's an angry black man.
"And I dare not scream racism because it's politically incorrect to scream racism. It's not cool, because Obama is President."
You don't have to dig very deep to find reasons for Daniels's barely concealed anger and frustration. When he was eight, for instance, he witnessed his father being racially abused by a white man he thinks was his dad's boss. Even as a child, he knew it was wrong.
"We got in the car and I screamed, 'Why would you let him talk to you like that?' and he punched me in my face." His father, a police officer who was shot dead when Daniels was 15, often hit him. "But I love him. He was a victim," the filmmaker says softly.
"I think that African-American men in the 1960s weren't really men - they were castrated - and he knew no better. It comes from slavery: we were beaten and then those people learned to beat their kids and so on."
Intriguingly, his follow-up to Precious originally was going to be Selma, a drama set during a pivotal moment in the civil rights movement in America in the 60s, but it collapsed.
He couldn't let Selma go completely, though, and ideas from it bubbled over into The Paperboy, which is set in the same era, as Daniels tried to inform the material with his own experience. This is the only way he knows how to work. "I cannot tell a story unless I know it. I can't talk about the characters and tell the actors what to do unless I know it, and I know the truth. If I don't know it, I don't do the movie."
Thus Yardley (David Oyelowo), a white character in the book, became black in the movie. An abrasive, chippy type, he cannot be himself because of racism.
"Yardley is me," says Daniels, "and [like him] I did what I had to do to get where I wanted to be." Like the character, too, he had white lovers who were racked with shame after sleeping with him. "They were attracted to me and they hated themselves," he says.
Daniels's films typically tackle sex and sexuality frankly and directly. In his own life, understanding his homosexuality from a young age helped give him the determination to escape the world of limited opportunities that he grew up in.
Daniels has got to where he is today through sheer determination and resourcefulness. His life has made him fearless and given him the strength of character not to be crushed by setbacks. Despite the failure of Selma, he's pressed ahead with another passion project, The Butler, about a black White House butler who served eight American presidents through three decades. Finding funding for this epic "black Forrest Gump" again proved difficult, and for a long time its future hung in the balance.
"White America doesn't want to know about the mistreatment of us in the 60s and slavery. They choose to forget about it," Daniels insists.
He didn't give up, however, and eventually got The Butler into production with independent financing. People can knock him down, maybe, but they can't knock him out.
"I dodged physical bullets. I dodged an HIV bullet in the 80s. I dodged being told I was nothing by my dad. I dodged the racism in Hollywood. I have survived. I will continue to survive. It's my instinct. It's what I know how to do until I die."