The Britney Spears and Fred Durst mystery (did they so much as date, or was the whole thing in his imagination?) deepened Thursday morning when the Limp Bizkit frontman discussed his reputedly self-declared professional and personal relationship with the pop princess on Howard Stern's syndicated radio show.

"I swear on my son Dallas's baby blue eyes I was telling the truth (about his relationship with Spears)," said Durst, 31, who was described by MTV News as being groggy when he talked to the shock jock. (Durst said he'd been out late the previous night.)

Stern, 49, of course, did not hold back on pressing him for dirt on Britney, 21 -- despite a recent statement from Spears's publicist saying of Durst, "It's sad that he's decided to make up stories, and the situation feels very junior high school."

"This (relationship) went on for a little while, that's what's pretty unbelievable about this crap she's saying," Durst said, after Spears denied any relationship.

"It wouldn't have been kiss and tell if I hadn't been responding to my fans," Durst said, referring to oblique references he had made about a budding friendship with Spears on his band Web site.

Pushed further by Stern on the air, Durst claimed that after two or three nights of collaborating on tracks for a future Spears CD, she invited him back to her Los Angeles home, accompanied by a group of her family members and friends.

Stern being Stern, he asked Durst if he spent the night.

Replied the musician, leaving his answer wide open to interpretation: "That would be uncool for me to answer."

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