Regular diners at the Dolley Madison Hotel might have suspected something when they went to the hotel entrance and found it locked -- at high noon.

Mechanical problems in the kitchen, an employe said. Oh, the oven's not working? "Everything's busted." Would they be open tomorrow? "It's going to be busted all week."

Back to the office for a phone inquiry about lunch. Nothing until the 10th? "The hotel is very occupied, we're all filled up." There's no way to make a reservation? A whisper. "You can't, you see, because the Rolling Stones are here!"

"It was made clear to us that we are not to give out any internal information," says the clerk behind the reception desk of this sedate and unlikely rock 'n' roll hotel. With a clerk like this, Nixon could have covered up Watergate.

"Yes, they're staying here, they've rented the rooms, they are being treated like everybody else," says an elderly managerial type. They've rented 44 units for their entourage of 60 people, which means they've rented the entire hotel? "So far," he says. Maybe the Brink's armored truck outside indicates they're thinking of buying it, too. Maybe it's a security deposit; some of those British bands have been known to be hard on a hotel.

"That was years ago," says a manager, knowledgeably, "when they were wild. They've mellowed, of course. They're making lots of money now; they got smart, too."

"Hi, I work for my high school paper and I've been assigned to interview the Stones. Do you know how I can reach them?" The caller sounds awfully nervous, with a don't-ask-me-my-name-or-school tension discernible between the heavy breaths. One wants to ask if she was even born when they first became stars. She hangs up before a suitably evasive answer forms. Can't give no satisfaction.

The Stones rolled in Sunday night, according to one security person at the Dolley Madison. "We don't want anybody to know that they're here, basically."

It may be hard to keep things quiet. In Syracuse, N.Y., a security man was in his room watching the local news when he suddenly saw the very hotel he was inside of looming larger and larger on the screen. A local station was doing a live broadcast from "just outside the Stones' hotel."

There will be no room at the inn until Thursday; there will be no entry, either. The Stones have a security apparatus that the Secret Service could smile upon. "They're awfully nice," says Marshall Coyne, owner of the Madison and Dolley Madison. "I don't know them, I've never heard them." Marshall Coyne may be the only one who hasn't.