James Caan was all smiles with famous friends Sly Stallone, Dennis Quaid and Sugar Ray Leonard out on the golf course, but these are dark days for "The Godfather's" Sonny Corleone. In an "Extra" exclusive, James spoke from the heart for the first time about the breakup of his marriage.

"My wife and I had a problem," he admitted to us. "That's unfortunate when children are involved."

Caan also opened up about his battle with addiction. "You see what bottom is," he said of his struggle.

During the Second Annual James Caan Classic at the ultra-exclusive Sherwood Country Club just outside of Los Angeles, Caan and his famous friends rallied to raise money for Impact House, the tough rehab center that helped Caan get clean nine years ago.

"I was a cocaine addict and it got me off, finished me," James said of the center.

It was around that time that the "Las Vegas" star met and married his fourth wife, Linda. But sadly, after two sons and nine years together, Caan filed for divorce just last week. "We were, unfortunately, fighting," he said. "And that's a very unfortunate thing."

And one of Hollywood's most famous tough guys wasn't too happy when the press broke the news minutes after the papers were filed: "I didn't have a chance to talk to my kids, you know, which I had planned to do."

But now the 66-year-old screen legend plans on a peaceful transition, telling us, "We're going to be much better friends than we were husband and wife; that's my goal."

And despite his divorce, Caan confessed he'd walk down the aisle again. "In a heartbeat," he revealed. "I believe in it, but right now my head is with the children."

But out on the golf course, James focused on fundraising for Impact House, which he and his brother, Ronnie, help run after both going through the program that Caan credits with saving their lives.

"It's really not much they're asking you to do," Caan admitted. "All you do, you go to a meeting, you eat, pretty soon I go, 'This is a pretty good gig.'"