Harrison Ford arrives at the Jules Verne Adventure Film Festival Tributes held at the Shrine Auditorium on October 6, 2006 in Los Angeles,Ca.[AP]

HILO, Hawaii (AP) ¡ª Harrison Ford, who turned 65 Friday, still fits into Indiana Jones' tight trousers.

Many fans are curious to see if, 18 years after "Indiana Jones and the Last Crusade," Ford can live up to the physical rigors of the globe-trotting archaeologist in the long-awaited fourth installment of the epic series.

Producers of the adventure, currently being filmed on Hawaii's Big Island, say there's no need to worry. Ford is as fit as ever.

"I have to say, he looks amazing," said Kathleen Kennedy, the film's co-executive producer, along with George Lucas. "He looks fantastic in the outfit."

Actually, Ford knew the hat would still fit but wondered if he could still squeeze into the pants. He did.

The action star, who first introduced Indiana Jones, sporting his fedora and cracking his bullwhip, in the 1981 classic "Raiders of the Lost Ark," is actually doing many of his own stunts in the latest film.

"He's doing them, he just has a few more ice packs and a few more massages," Kennedy said.

"And a lot of Celebrex," producer Frank Marshall added.

The movie just completed the first of three weeks of filming in Hawaii, after spending a week each in New Mexico and Connecticut. The lush areas surrounding Hilo are filling in as a South American rain forest.

Lucas and director Steven Spielberg have not released the title of the film, scheduled for release May 22, 2008.

The filming has created a buzz on this normally sleepy island, known for macadamia nuts and premium Kona coffee. It's the most action since nearby Kilauea volcano rumbled to life in 1983. Like Indiana Jones, the still-erupting volcano has been an attraction ever since.

In the privately owned jungles of Keaau, one of the movie locations, two colorful signs that were drawn in crayon and decorated with balloons were displayed at Liberty Christian School.

One welcomed the cast and crew of the film. The other read: "Happy Birthday, Harrison Ford."

Janae Pacheco helped draw the sign, even though the 8-year-old student admitted not knowing Ford or seeing his movies.

"Not exactly," she said, when asked if she knew Ford. "But my teacher does."

The film's biggest action sequences are being filmed in Hawaii. Marshall compared one scene to the thrilling, white-knuckled truck chase in the desert in "Raiders."

"It's that level," he said.

Hawaii will be featured in about 20 percent of the film. About half will be from sets in Los Angeles. The Aloha State was also the backdrop for portions of "Raiders of the Lost Ark."

Ford, Lucas, Spielberg, Kennedy and Marshall all worked together on what till now has been the trilogy. So, it was a homecoming of sorts.

"We're having a great time. It's so much fun being together," said Marshall, who has produced more than 50 films, including "Poltergeist," "Gremlins," "The Goonies," "The Color Purple," "Back to the Future" trilogy, "The Sixth Sense" and the "Bourne" trilogy.

"Nobody's worried about their careers any more," he said.

The latest Indy adventure is set in the 1950s and, in addition to Ford, stars Shia LaBeouf, Cate Blanchett, Ray Winstone and Jim Broadbent. One popular character not in the line-up is Sean Connery, who played Indy's father.

"We would've loved to have Sean do a cameo-type part in this but he's very much enjoying retirement," Kennedy said.

She promised movie fans, who have patiently waited since the 1989 "Indiana Jones and the Last Crusade," would get the same level of excitement as the previous three films.

"The cleverness, the humor and the tone of Indiana Jones is very much alive and well in this movie," Kennedy said.

The producers are being very tightlipped about the movie, and the remote sets are well guarded, leading to rampant rumors on blogs and chat sites.

It took some time to get to the fourth film, partly because of the schedules of Spielberg, Lucas and Ford. Plus, they knew they had to deliver another hit.

"The bar was pretty high," Kennedy said.