Twentieth Century Fox Animation has set Jimmy Hayward and Steve Martino to direct its CGI-animated adaptation of the Dr. Seuss classic “Horton Hears a Who.”

Fox has slotted the film for a spring 2008 release. Pic is being produced by Blue Sky, makers of “Ice Age” and “Robots.”

The script has been written by Ken Daurio and Cinco Paul, and storyboarding has just begun under the supervision of Fox Animation president Chris Meledandri and Blue Sky’s Chris Wedge, both of whom are producing.

Exec producing will be Audrey Geisel, Theodor Geisel’s widow, who sold Fox both “Horton” and an option for a sequel based on “Horton Hatches an Egg.”

Hayward spent a decade as an animator of such Pixar films as “Toy Story,” “Finding Nemo,” “Monsters, Inc.” and “A Bug’s Life.” He was supervising animator on “Toy Story 2” and first worked with Westchester-based Blue Sky as a consultant on “Robots.”

His role on that film grew to story consultant and additional scene direction.

That’s where he met Martino, who was art director on “Robots.” Martino came to Blue Sky after helping to establish such animation houses as MetroLight Studios, which won an Oscar for its visual effects work on “Total Recall.” The Emmy winner then formed Click 3X L.A., where he was animation director before joining Blue Sky in 2002.

Martino and Hayward have used their access to Mrs. Geisel to delve into Dr. Seuss’ notes and letters explaining his visual inspiration for the Horton character and his world. They’re working with visual development artists Dice Tsutsumi, Sang Jun Lee and Sean Tann, and full scale animation will begin by the summer.

While Geisel’s “Cat in the Hat” and “How the Grinch Stole Christmas!” became live-action vehicles for Mike Myers and Jim Carrey, Meledandri thinks the 3-D CGI format is the best forum, one that makes a star of Seuss’ richly imagined visuals.

“He had one of the greatest imaginations, and opening a Dr. Seuss book as a child or an adult meant entering his unique world,” Meledandri said. “We always felt that there were inescapable limits on how successfully live-action filmmaking could translate Geisel’s vision to film. With CG imagery and the amazing talents of the artists at Blue Sky, we have the opportunity to truly transport an audience into the enchanted world of Seuss and, for 80 minutes, make then believe that it really exists.”

Fox Animation veep John Cohen is shepherding the pic with Meledandri. Fox releases Blue Sky’s “Ice Age 2: The Meltdown” March 31.