Marc Benioff, Silicon Valley's greatest publicity whore, had the cops called on a Wall Street Journal reporter, and has been telling people he also set a private investigator on her tail. And all for daring to write a story on the new mansion the Salesforce.com CEO was building in Hawaii. The Journal avoided mention of the clash when the piece went to print. You may remember the reporter's name, Pui-Wing Tam. Yes, she's the same person investigated by another Silicon Valley company, Hewlett-Packard, after she wrote about the board's unhappiness with CEO Carly Fiorina. This paranoid behavior by Silicon Valley execs is becoming a habit.

This is a Valleywag exclusive. For the juicy details:

Pui-Wing Tam, one of the Journal's more enterprising reporters, traveled to Hawaii's Big Island to sneak a peek at the five-acre estate Benioff was putting up on by the shore. No great scandal. Benioff made his money legitimately, with the 2004 public offering of Salesforce.com, the online sales management service he founded. The journalistic interest was pretty innocent: depict the lavish lifestyle of one of Silicon Valley's most colorful figures, the bungalow-style buildings, the thatched roofs, the lagoon-style pool, the 7.606 square-foot living area.

But I've heard from several Silicon Valley insiders that Benioff, for once outraged at press interest that he had not himself sought, had the police called on the Journal reporter. A spokesman for Dow Jones, which owns the Journal, emailed for comment, confirmed Pui-Wing was obstructed by construction workers on the Benioff property when trying to drive from a neighboring property out to the main road.

The Dow Jones official, Robert Christie, told Valleywag that Pui-Wing had never been charged, but refused to confirm that the police were called, nor whether the Journal reporter was arrested, before being released without charge. Outcast PR, which represents Salesforce.com and employed Benioff's fiancee at the time of the incident, did not return a call for comment.

No hint of the incident made it into Pui-Wing's eventual piece on Benioff's Shangri La. All Pui-Wing wrote: Mr. Benioff, through a spokeswoman, declined to comment for this article. The most plausible explanation for the omission: Benioff said he would not press charges in exchange for the Journal's discretion. Dow Jones would not comment on any agreement between it and Benioff. Benioff is a good source for the Wall Street Journal, as he is to other business publications, but any arrangement between them would be extremely controversial.

Bizarrely, Benioff has also boasted to people of setting private investigators onto Pui-Wing Tam. If he indeed did, which is admittedly questionable, that would mean the Journal reporter had two separate teams rifling through her trash earlier this year, one hired by HP and the other by Benioff. Someone should buy the film rights: this could be a comedy.

Benioff's obsession with privacy is all the more absurd because the Salesforce.com boss has aggressively sought press coverage for his company, and, when it has suited him, boasted to reporters of his celebrity friendships and extravagant lifestyle. He's seated next to celebs like David Bowie and Uma Thurman at charity events. He's close to Steve Jobs. In Benioff's office, at least until recently, he had a photo of himself with George Bush, to whose campaign he donated.

To be sure, Benioff has his charms. He's larger than life, in the way few Silicon Valley execs are; he does give generously, even if loudly, to charity; and he has a spiritual side, judging by the numerous press references to his liking for yoga and eastern mysticism. When in Hawaii, when not interrupted by nosy reporters, he says he enjoys swimming with dolphins: I like interspecies communication.

But Benioff's wild over-reaction to Pui-Wing Tam's incursion gives credence to his many critics, who are happy to bitch about him off the record. As one dinner party companion said of him, he's one of the few surviving assholes from the last boom. Some people don't grow, they swell.

For background reading, check out the stories below, from which I have liberally borrowed. This story isn't over, trust me, so keep an eye on our dedicated Benioff feed. I'm assuming that the Journal will now be forced to make a fuller comment, and so will Benioff. Tips to the usual place. Be careful what you put in the comments, or Benioff might stick a P.I. on you.

• A reporter's story: how H-P kept tabs on me for a year [Wall Street Journal]
• As tech rebounds, software mogul builds in Hawaii [Wall Street Journal]
• The fresh prince of software [Fortune]