With six years having passed since the last time he was onscreen -- in Rush Hour 2 -- Chris Tucker gets a lot of "Where've you been?"

Where's he been? Making humanitarian visits to Africa for starters. And testifying at the child molestation trial of his friend Michael Jackson. And performing standup. And in the closest thing to a Paris Hilton moment, he was popped for speeding in Georgia -- claiming he was late for church.

So Tucker's been busy enough. He just hasn't been saying yes to movies. And a reported paycheque of $25 million to reunite with Jackie Chan for Rush Hour 3, buys a guy a lot of "No" power.

"I've turned down a lot of silly comedies," Tucker says, "scripts that never even got made. A lot of these projects, it's like nobody really wanted to do them but they push on anyway.

"Rush Hour was different from the beginning. It has a real tone to it, a great set up. And from the first movie on, all the comedy came from a real place."

Not that he was that confident the first time he met his co-star 10 years ago. "The first time I met Jackie, we had a meeting in the States. And I was talking about doing the movie and he never spoke the whole time. And I asked the director (Brett Ratner), 'Why is he not talking, man? Does he not speak English? How'm I going to be funny if he don't speak English?

"And the director was saying, 'Don't worry, he'll speak English by the time we start filming.' And I'm like, 'What?' Actually, he did speak English, and it was just his culture to feel me out and get to know me by listening."

Still, in the inevitable blooper reel during the Rush Hour 3 closing credits, Chan's mangling of various lines of dialogue remains a source of laughs. "His English is actually pretty good now. But he still messes up a lot," Tucker says, segueing into a Jackie Chan impression. "He'll get mad and say, 'What? I don't know that word! Why you give it to me? You try speak Chinese!' "

In producer-speak, the first Rush Hour had Chan as a fish-out-of-water -- a Hong Kong cop working in L.A. The second had Tucker as the fish-out-of-water L.A. cop in Chan's Hong Kong 'hood.

In the third, Tucker's character James Carter and Chan's Inspector Lee are both fish-out-of-water, following the trail of an international Chinese mob boss to France.

"France was actually my idea," Tucker says. "We were kicking around ideas and they said, 'Where do you want to go?' and it just popped into my head to say France."

Still, doing a third Rush Hour wasn't a slam-dunk. When he was first asked, the movie didn't even have a script.

"I approached it like any other project, the first question being, is it the right thing to do? Do my fans want to see it? Finally, we got a script that was good enough that I knew we could make it better once we started filming.

"So then it was right back in it. I went on the road and did a 20-city standup tour just to warm up and get my timing down. And as soon as we were on the set, it was like we made Rush Hour 2 yesterday. Jackie stays in great shape, and he's always ready to go."

Tucker doesn't regret the six-year layoff. "I've been doing a lot of personal stuff, coming up with new ideas. And working on my Foundation, going back and forth from Africa really changed me as a person."

Tucker's African crusade -- and his Chris Tucker Foundation which benefits South African youth -- goes back to 1998, when he visited South Africa to promote the original Rush Hour.

"I went back on my own in '99 because I didn't get a chance to really see the place. People was telling me, 'you didn't go to Soweto? You gotta go there, you gotta go here.' "

Soon he was making regular trips and taking part in "fact-finding missions" in Ethiopia with ex President Clinton and in Uganda with Bono.

"Those are just the two coolest guys, very worldly, smart guys. Clinton just has a brilliant mind, and he's all about beating poverty with the economy -- giving people the ability to make money and giving them hope, so that they can buy the anti-viral drugs they need to beat HIV.

"It was the greatest experience, I learned so much about what went on around the world. You're going to places where there's no clean water 'cause an animal died in the water supply, or going to an orphanage full of babies, with just two nurses to look after them. I used to brush my teeth with bottled water, and I don't anymore because I appreciate something as simple as a glass of water.

"I was the first one going to Africa and since then a lot of people have started coming. Now you've got Don Cheadle and George Clooney, Jay-Z and Alicia Keys in Africa. Angelina Jolie and Brad Pitt. I've been going to (the World Economic Forum in) Davos for years and the first time I met Brad Pitt was at Davos."

Closer to home, Tucker says he's proud to have been able to step up for his friend Jackson during his trial. "I do talk about Michael Jackson's friendship onstage. I admire him, I think he's the greatest entertainer that ever lived. He's done stuff nobody else has come even close to.

"I was subpoenaed (by the defence) because I knew the family. They were approaching a lot of celebrities for money at the time, and I was one of the ones they approached.

"So I had to come and testify and I felt really good about it. Someone's in trouble, you're going to deal with it and try to help."

The $25 million cheque having cleared, Tucker could easily take another six years off from movies. Instead, he's heading back to the set before the year's end. After a standup tour in September and October (with dates in Toronto "and possibly Montreal"), Tucker plans to start filming the comedy Mr. President "where I'm going to play the first Black president." I point out that Chris Rock did a movie, Head of State, with the same premise. "He did do one like that," Tucker agrees, "but this be my version, and the difference will be, it'll be the way I play it. People will be seeing Chris Tucker as the president. It'll be funny and it'll be good."

There's also Rush Hour director Brett Ratner's next project, an as-yet-untitled buddy movie starring Chris Rock and Eddie Murphy. The director did ask Tucker if he wanted in, "and I told him I wasn't interested.

"He could always show me a script later, and if it's good I could change my mind. We'll see."