The title of "In Gay Company," an off-off-Broadway musical revue now at Columbia Station, is probably warning enough for those who need to be warned. With lyrics and score by Fred Silver, it treats love, lust and loneliness in the male homosexual demimonde.

The National Cabaret Theater Company's production, with a cast of five singing 19 songs, makes for diverting entertainment, no matter your orientation.

The opening number has four tuxedoed gents and a lady waxing wistful about the past: "When Judy Garland wasn't yet our patron saint . . . When S & M were merely sizes . . . There's no more risk in being risqu,e."

Over the next 80 minutes, they sing and toe-tap their way through such risky business as groping strangers in movie theaters, as in a ditty called "Loews Sheridan Square"; longing for companionship, as in a song that goes, "I want a small town boy who wants a small town boy"; and having sex in public lavatories.

"St. John's john I've heard is quite divine now," asserts a tune titled "Beginner's Guide to Cruising," which also advises, "Stay away from the BMT!"

Yet even when walking on the seamy side, the show rarely sheds its witty veneer. Sometimes it bubbles with bawdy insouciance, making "gay" seem really gay; at other times it's as cool and sharp as an icicle, as when one character laments, "Those empty feelings stab at me . . . Tonight you are lovers, tomorrow not even friends."

The cast members, directed by John Moran, are all adequate cabaret performers, though John Edward Niles' piano playing lacks precision and nuance.

The rotund Ray Chesnick Jr., romping about in drag, brings fey hamminess to his "Lament for a Decoy Cop." The gap- toothed Gary Johnson, whose air of mischief is alternately boyish and bitchy, sings on- key in a humorous whine. He's especially effective in a tune about cruising an outdoor concert, in another about similar pursuits at the Metropolitan Opera, and in a mocking number titled, "You Really Ought to Get Married" -- for which he leaves the stage to kvetch at particular patrons.

An emaciated Andy Warhol blond, a la Edie Sedgwick, might have been better- suited to the lady's role than ample Melissa Berman. Her smoky, full-throated rendition of "The Wasp Blues" just ain't convincing. But Berman's reliable singing often keeps the music together. IN GAY COMPANY -- Fridays and Saturdays at Columbia Station through August 27.