But as Mr Mandelson will attest, coming out at work is just the beginning. It opens the floodgates to Chippendale calendars every birthday, a rabid interest in your sex life and immediate elevation to honorary girl among the office gossip circle. Like pet Gonks and office mascots, the single homosexual man can become the pet gay. He is contractually obliged to camp it up outrageously on demand, always have a copy of Hello! in his top drawer and provide a shoulder to cry on at all times.
"At first, I felt immense relief when I finally told my PA I was gay,", says solicitor Ben Shaw. "But it's sometimes hard to maintain a professional relationship when she starts treating me like her best girlfriend and I find myself nodding in agreement when she sobs, 'All men are bastards'."
Offices may have become cooler about sexual orientation but coming out to co-workers is still a dilemma for every gay man and lesbian. It's a bit like telling everyone at the office party you can do the splits. You will be asked repeatedly to demonstrate. Once out, you are expected to act as tour guide for co-workers to the sexual twilight zone you are presumed to inhabit.
"When George Michael was caught trying to pick-up a policeman in LA, I was expected to be the expert witness at work," says Nathan Penfold, an IT specialist. "Suddenly I found myself defending cottaging (sex in public toilets) as if I were Joe Orton's lawyer. I suppose you feel somehow responsible for the straight world's perspective on gay life; you go on the defensive."
Pearce Roberts is an ad sales manager in the women's magazine market. He says: "It is interesting that a career like women's magazines attracts strong women and gay men. At one magazine, the entire team were women apart from me and I had a hoot. You are the exception and you are made to feel special. I don't hide my sexuality but neither do I flaunt it inappropriately. I must say now I've noticed one gay man in the office who has just come out and he might as well hang a sign round his neck. He calls everyone "she" and is a real screamer. I understand why he wants to tell the world but I don't think he is doing himself any favours in the long run."
This is the rub. You want to come out, be comfortable with your sexuality and not blush every time someone shouts "It's your boyfriend on line one!" But you are also aware that celebrating your sexuality does not stretch to calling the MD "Miss Thing" or behaving like Mae West every time a pretty boy comes up from the post room. Remember that John Inman in Are You Being Served? was a pet gay, and pet gays never make it into senior management.
Textile designer John Bowman says, "For gay men and women born in the sticks, with little or no gay contact, puberty is delayed until the late teens when we all tend to run away to London. Like many gay men, I worked the bars in Soho and sowed my wild oats: slept around, camped it up, did the clubs and stuffed drugs up my nose. I needed to come out with a bang in a totally gay-friendly environment before I could get a 'proper job' and calm down a bit."
There is an element of "Why should I?" defiance by gay men, who do have to moderate (or put a lid on) their personalities at work. So certain career paths where gay is the rule rather than the exception still attract a disproportionate number of homosexuals. Cliched as it may be, fashion, PR and pockets of show business and media are all pink collar jobs. They are VIP room careers controlled by strong women and gay men - a combination that terrifies straight men more than a vasectomy. Robert Dunne is a wig- maker for an opera company. He says, "I always preferred hanging out with the creative people at school, smoking, gossiping and talking about frocks. It stands to reason I would look for the same environment in the working world."
However, in stalwart pink collar professions, gay men seem to be more secure than lesbians. This week Ellen DeGeneres and Anne Heche, probably the most famous lesbian couple since Gertrude Stein and Alice B Toklas, left Hollywood for San Francisco. Since DeGeneres' very public outing on her TV show Ellen, the actress claims she has been blacklisted by the industry. It might not have occurred to DeGeneres that her appeal was due to an in-joke. Everyone but the character herself knew "Ellen" was gay. When "Ellen" cottoned-on, the joke fell flat. DeGeneres was persecuted, not for being a lesbian, but for failing to make her audience laugh.
If a high-visibility lesbian like DeGeneres feels persecuted at work, then the message sent to lesbians is not a positive one. Stonewall's 1993 survey of 2000 gays and lesbians reported 48 per cent of respondents were harassed due to sexual orientation. 24 per cent had avoided selecting certain professions for fear of discrimination and two thirds concealed their sexuality from people at work. "I have been under pressure to declare my sexuality," says trainee psychotherapist Anne. "Colleagues seem to think I owe it to future patients that they are aware of what is essentially my private life. The issue here is not concealing my sex life from colleagues. It is whether I consider that this information - my private life - has any bearing on my proficiency as a psychotherapist. I personally think it does not."
A burgeoning gay service industry in major UK cities has begun to remove the question of "outing" at work. These gay-friendly businesses directly appeal to the pink pound: for example, cab firms like London's Freedom Cars, legal advisers like Ivan Massow Associates and anything in between from plumbers to dentists. These businesses thrive on the premise that gay people are more comfortable doing business within each other. Freedom Cars driver Drew says, "Most of the drivers have parallel careers; musicians, writers, actors. So if you've got to supplement your income then why not make the experience as pleasant as possible by working with other gay people?"
In January 1998, gay glossy Attitude wrote a celebratory feature about men at work. "We know that some provinces of the fast-moving, glamourous worlds of fashion, television and, yes, ahairdressing, are entirely gay," says Attitude, "but these days gay people are getting everywhere."
Gay people always were everywhere - but now the secret is out.
Some names have been changed.