New York  - It's been so long since JD Salinger published anything that it's surprising to realize he's still around and celebrating birthdays - his 90th on New Year's Day.

But for a writer whose last published work was in 1965, Jerome David Salinger's fame has hardly faded. His most famous work, Catcher in the Rye, which foreshadowed the youth rebellion of the 1960s, has remained in print since it first appeared in 1951.

As early as 1944, Ernest Hemingway recognized Salinger as having a "helluva talent." The two met in Europe during World War II, where Salinger served in the US Army.

Salinger's most famous character was Holden Caulfield, the foul- mouthed 16-year-old prep school reject who rebelled against the hypocrisy of adulthood. Caulfield, who has been compared to Johann Wolfgang van Goethe's Werther, first appeared in 1946 in a short story in the elite New Yorker magazine, under the title Slight Rebellion off Madison, and then was fleshed out in Catcher in the Rye - Salinger's only novel.

Salinger's last published work appeared 43 years ago in the New Yorker, a novella Hapworth 16, 1924, part of his series on the Glass family.

But the Glass series remains unfinished, and whatever might be going on in his life as he turns 90 remains a closely held secret.

Repelled by the demands of almost cult-like fame that came with Catcher and his successive works - Nine Stories in 1953 and Franny and Zooey in 1961 - Salinger retreated into an isolated life behind a high fence in Cornish, a small village in the hills of New Hampshire in the US north-east.

"I love to write. But I write just for myself and my own pleasure," Salinger told a New York Times correspondent in 1974, in a telephone interview. "There is a marvelous peace in not publishing."

Most of what is known about the secretive author comes second hand. A former lover, journalist Joyce Maynard, described in her 1998 memoir At Home in the World how Salinger sat every day in blue overalls at his typewriter and wrote volumes, then locked them away carefully every night.

"I can take society well enough, so long as I keep my rubber gloves on," she quotes Salinger as once saying.

But Salinger was already 53 and Maynard only a 19-year-old student as she lived with him for less than a year.

More reliable perhaps is the image of Salinger that emerges from a book, The Dream Catcher, written by his daughter, Margaret, in 2000. She describes him as a wonderful father in her childhood who mutated into a pathologically self-centred man later in life. No one and nothing could disturb him at work. She only ever entered his work room and bedroom once or twice in her life, she writes.

In the eyes of his family, Salinger's refusal to publish was founded in his fear of criticism, his daughter wrote.

The suggestion appeared to have some basis in fact. Salinger had decided to release his Hapworth novella in book form in 1997 through a small publisher, Orchises Press - a sensation that was advertised on the fledgling Amazon. com and highly anticipated in the literary world.

But long before it reached print, critics who were familiar with the work since 1965 lambasted it as a bitter, illogical story with little merit. The book was withdrawn from publication.

Asked this week about the reasons for the withdrawal, the Orchises publisher Roger Lathbury told Deutsche Presse-Agentur dpa that he could not comment on the reasons. He also dismissed reports that Hapworth could be published in 2009. (dpa)