WWW- When it came to digging dirt on a star, no info was too gamy for Hollywood private eye Anthony Pellicano – especially if that star was Sylvester Stallone.

On Monday, federal prosecutors unsealed an indictment charging that Pellicano had invaded the privacy of Stallone, among almost a dozen other people.

Former Pellicano legman Paul Barresi says he personally “never used any illegal means” to gather information for his boss. But he says Pellicano definitely hungered for anything that might embarrass the “Rocky” star.

Barresi says Pellicano relished a 1991 tape on which Naomi Campbell allegedly pleaded with one of Stallone’s security guards to have the actor call her.

“If he doesn’t call me, I probably will have taken the whole [bleeping] bottle of Valium by the time he gets back,” a woman, supposedly Campbell, says on the tape (which we’ve heard).

When the security guard tells the woman that’s a bad idea, she shoots back: “I’ve done it before. Don’t worry. [The paramedics] always get me in time.”

The speaker sounds like she may be goofing around. Campbell’s rep had no immediate comment on whether that was Naomi.

Stallone’s attorneys have alleged that any recording was made by a former employee without Sly’s knowledge.

That same employee later claimed Stallone used to beat his dogs. The allegation also found its way into Pellicano’s file on Sly, according to Barresi.

Barresi said he also supplied Pellicano with the results of a lie detector test corroborating the employee’s claim. But Stallone’s rep called it “an outrageous fabrication.”

Why was Pellicano out to smear Sly?

According to this week’s indictment, Pellicano wiretapped Stallone in February 2002 – the same month the actor sued his former business manager Kenneth Starr, whose attorney Bert Fields sometimes relied on Pellicano. (Fields has denied knowing of any wiretapping.)

Barresi says Pellicano talked to him about Stallone in 2002, but suggests Pellicano’s motive went beyond the Starr lawsuit.

“He would dig up dirt on any celebrity who might be a potential client,” Barresi tells us. “Then he would tell the celebrities about the bad news floating around, and he’d get them to hire him for protection.”

A lawyer for Pellicano did not immediately return a call.