"Some jealous husband has kissed my glasses to keep me from seeing his wife," said Maestro Mstislav Rostropovich, cleaning off the smudge.

Whoever she was, that wife must have been the only one the flamboyant conductor of the National Symphony Orchestra missed last night. Unashamedly puckering up to await their turns were socialites and secretaries, businessmen and lawyers, Republicans and Democrats, just about anybody who loves music and especially the brand dispensed by Rostropovich.

"We call this a kiss-through," said Joanne Steller, NSO director of public relations and marketing, who led the way through 450 symphony lovers celebrating the opening of the orchestra's 55th season, at a postconcert party in the Kennedy Center Atrium.

"The artist's entrance!" Rostropovich called out to Virginia Mars, the orchestra's president, who had accompanied the orchestra on three weeks of its four-week European tour.

The evening had an international theme, focusing on Italy, Greece, Yugoslavia, West Germany, Belgium, Switzerland, France, England and Ireland -- all of the countries the orchestra visited. Several of the ambassadors joined Defense Secretary Caspar Weinberger in the Presidential Box at the concert.

Hosting the party was Raleighs President Neal J. Fox, who said that because Raleighs is a Washington institution he wanted it to be "heavily involved in the community."

"There's a tendency in this city, especially by local companies, to focus on sports -- the Washington Redskins, the Washington Bullets, the Washington Caps. I'm not pointing any fingers but ofttimes local companies have not been as supportive of the arts and a national treasure like this orchestra," said Fox, NSO's newest board member.

Joining Rostropovich, Mars and Fox to greet guests was the NSO's new executive director, Stephen Klein, who called the tour the "most phenomenal thing I've ever seen, the most triumphant I've ever known."

Edging out of the crowd was Weinberger, saying the Pentagon and White House are in "full communication" despite reports that he had been upset by the administration's initial endorsement of the Israeli raid on the Palestine Liberation Organization headquarters in Tunis.

Asked whether a hot line might help everybody stay in touch, Weinberger said, "We have one, but people are occasionally out of town, things like that. No, I was out of town today."

When someone suggested that perhaps Rostropovich should negotiate with Soviet leader Mikhail Gorbachev in Geneva next month, the maestro beamed: "I'm ready."

Turning serious, he was confident President Reagan can do the job and that he should "just continue" being himself when he meets Gorbachev.

"I love President Reagan," said Rostropovich, who left the Soviet Union 11 years ago when Gorbachev was "completely unknown." "I think this conversation is the most important moment of the whole world, for the future of the world. President Reagan must not be coming like that [he wiggled his hand side to side] but straight. I trust President Reagan."