For all those "Masterpiece Theatre" fans, host Alistair Cooke and several stars from the hit PBS series will be in town for a private 20th-anniversary party Monday at the State Department. Since the party, sponsored by Mobil Corp., is for oil company executives, television critics and public broadcasting officials, there will be little opportunity for fans to see their favorite stars unless they drop by the Grand Hotel, where the stars are staying.

Mobil, which is now headquartered in Fairfax, has sponsored "Masterpiece Theatre" since it began with "The First Churchills" on Jan. 10, 1971. The series has won 25 Emmys over the years. Among the performers expected for the State Department dinner are Francesca Annis, Jeremy Brett, John Hurt, Geraldine James, Ian McShane, Jean Marsh, Keith Michell, Sian Phillips, Diana Rigg and Simon Williams.

Beginning Sunday, WETA will begin presenting selected episodes from some of "Masterpiece Theatre's" best-remembered series, such as "Upstairs, Downstairs," "The Flame Trees of Thika," "I, Claudius" and "The Jewel in the Crown."

Out and About It was a timely bit of good news yesterday for Lee Atwater, who learned that the title song of his album "Red Hot and Blue" was nominated for a Grammy Award in the category of Best Contemporary Blues Recording. The Republican National Committee chairman, who is scheduled for brain surgery Monday, was described as "thrilled" by the nomination. RNC spokeswoman Leslie Goodman said that "since music has always been an important part of his life and his biggest inspiration," the nomination couldn't have come at a better time. The song nominated is an original, co-written with Atwater's mentor B.B. King, and is up against recordings by such blues stalwarts as Robert Cray, Etta James and the Vaughan Brothers ...

What could be more fitting for the 50th anniversary of the National Gallery of Art than the gift of a 5-by-6-foot colorful painting of birthday cakes. The oil painting, by well-known contemporary artist Wayne Thiebaud, was presented to the gallery by the Collectors' Committee, the 50th Anniversary Gift Committee and the Circle, with additional funding from the family of the late art book publisher and collector Harry N. Abrams. It is to go on display March 17, the actual anniversary date of the opening of the gallery ...

In what certainly is an ironic twist, South African President F.W. de Klerk, whose apartheid reform program aims to break down the country's strict race barriers, may soon have a nonwhite daughter-in-law. The story could not be confirmed and de Klerk declined to comment, but a report in Die Burger said his son, Willem de Klerk, 24, would soon become engaged to Erica Adams, 22, who is classified under apartheid as colored, or a person of mixed race. The newspaper is recognized as having a good government connection. South Africans recognize four main race groups and between 1957 and 1985 were forbidden to marry or have sex across racial lines ...

Outgoing Ohio Gov. Richard Celeste, who has a conservative record on granting clemency, yesterday commuted the prison sentence of country singer Johnny Paycheck and ordered his immediate release. Paycheck, who has served nearly two years of a seven-to-9 1/2 year sentence, was convicted of shooting a fellow bar patron in the head. Celeste, whose term ends Monday, stipulated that Paycheck serve 200 hours of community service "and remain alcohol-free" ...

Jazz moves up a well-deserved notch with the creation of a Department of Jazz at Lincoln Center in Manhattan. Rob Gibson, who was named to head the newly created department, said that in five to 10 years "we should have jazz three nights a week at Lincoln Center, right along with the New York Philharmonic" ...