Jeffrey J. Steiner is the gazillionaire chairman and CEO of Fairchild Corp. Guests at his glittering 70th birthday party at the Rainbow Room on Saturday included Ivana Trump, Denise Rich and Carl Icahn.

The NYPD is a local law enforcement agency which arrested Kramer during the party for allegedly sexually assaulting a 13-year-old boy in the men's room.

"The police officer [was] informed by the victim that the incident transpired in the rest room, where the defendant grabbed the victim's groin area and stated 'high five!'" an NYPD spokesman told us.

The arrest occurred on the 65th floor of 30 Rockefeller Plaza around 11:35 p.m. The police report said Kramer was charged with "endangering the welfare of a child, sexual abuse in the second degree and forcible touching."

A Miami friend of mine was not in the least surprised by this development. "That's his thing - grabbing crotches," she said.

Kramer (who says he's 39 on his MySpace page, but turns 50 this month, according to the police report) has had rape charges against him dropped in the past. He is also notorious in Miami for an incident in which he threw a glass of wine in a homeless man's face.

The South Pointe developer was released without bail and has a May 3 court date.