rupert_everettActor Rupert Everett, 50, who has been openly gay for 20 years has some advice for gay singer Adam Lambert and any other show biz personality who is gay – stay in the closet.

The “My Best Friend’s Wedding” star says that Hollywood homophobia has kept him from becoming a leading man. He says that heterosexuals are cast as gays but gay men are denied the plum straight roles.

“It’s not that advisable [to come out] to be honest. It’s not very easy,” he told the UK’s Guardian newspaper. “And, honestly, I would not advise any actor necessarily, if he was really thinking of his career, to come out.”

Everett also believes there is a double standard in Hollywood. He noted that Heath Ledger and Jake Gyllenhaal were tapped to play gay cowboys in “Brokeback Mountain” and neither are gay.

“The fact is that you could not be, and still cannot be, a 25-year-old homosexual trying to make it in the British film business or the American film business or even the Italian film business,” he said.

The taboo seems to apply to women as well. Lindsay Lohan is no longer considered a lead romantic actress because of her gay fling with openly lesbian Samantha Ronson. Lohan is now said to be switch-hitting again.

Anne Heche also lost credibility as a lead romantic actress after she became involved in a lesbian relationship. But she has since married to a man and started working again. Openly lesbian Jody Foster, a top actress, has never played a romantic lead.

“American Idol” runner up Lambert was the latest to cause an uproar because of his overtly gay performance at the American Music Awards. He French kissed one male dancer and pushed the face of another into his crotch to simulate oral sex during his live performance.

The move subsequently cost him an appearance on ABC’s “Good Morning America.” Lambert had no apologies for his performance, and it hasn’t hurt his album sales.

But Everett still advises against it.

“It just doesn’t work and you’re going to hit a brick wall at some point. You’re going to manage to make it roll for a certain amount of time, but at the first sign of failure they’ll cut you right off,” he said.

And I’m sick of saying, ‘Yes, it’s probably my own fault.’ Because I’ve always tried to make it work and when it stops working somewhere, I try to make it work somewhere else. But the fact of the matter is, and I don’t care who disagrees, it doesn’t work if you’re gay.”

Everett does admit that his openness about his sexuality has afforded him personal happiness if not professional success. He’s glad he’s not one of the “plenty” of gay Hollywood stars still stuck in the closet.

“I think, all in all, I’m probably much happier than they are,” he said. “I may not be as rich or successful, but at least I’m vaguely free to be myself.”