Actor Rock Hudson says he's comforted that his suffering from AIDS "had some positive worth" in focusing attention on the deadly disease and helping sell out a celebrity gala to benefit fellow victims. "I am not happy that I am sick. I am not happy that I have AIDS, but if that is helping others, I can, at least, know that my own misfortune has had some positive worth," Hudson said in a letter to be read by Burt Lancaster during the black-tie "Commitment to Life" gala tonight at Los Angeles' Bonaventure Hotel. Hudson said he regrets being unable to attend but will be "with you in thought and spirit" . . .

There's another birthday in the first family. Lucky, that friendly, furry bear of a sheep dog, usually seen on the evening news pulling Nancy Reagan out of the presidential helicopter, will be 1 year old tomorrow. The fluffy mutt from the ostentatious-sounding breed name Bouvier des Flandres will spend her birthday weekend with the family at Camp David, where she will receive a gift-wrapped bag of doggie biscuits . . .

Washington women take heart. Mademoiselle magazine's list of 50 great catches did list a Washingtonian, who lives at least part of the time here. In the group of available men is Jason Korman, a 25-year-old college dropout who owns the International Wine Exchange. He has a winery in Petaluma, Calif., a house in Georgetown and a home on Long Island. And he probably doesn't care at all whether the White House wines are foreign or domestic . . .

The Farm Aid train may not have rolled east this week because of financing difficulties with Amtrak, but country music star Merle Haggard is planning a 3,000-mile train trip for the spring. The original plan had been for a trip from Bakersfield, Calif., to Champaign, Ill., where many country music celebrities riding on the train would perform at a mammoth concert. Haggard said planning is under way for another train in the spring that would leave the West Coast and end up in Washington, D.C., to focus attention on the plight of the farmers . . .

There will be some unusual customers at Powers Court, the dark-paneled, dignified restaurant in the Phoenix Park Hotel. The rock group Twisted Sister, not one of the more refined music groups, called the hotel yesterday to reserve space for a press conference there after testifying before the Senate Commerce Committee on rock lyrics. The restaurant is proud of its cuisine, but agreed to Twisted Sister's requested menu of pizza, popcorn, canned beer and Chips Ahoy cookies . . .