HE KEEPS GOING AND GOING AND . . . Between taking reservations at the Washington location of McCormick & Schmick's (1652 K St. NW; 202-861-2233) last Thursday, veteran restaurateur Mel Krupin took a few minutes out of his busy schedule to let us wish him a happy 75th birthday. What, you didn't know he was the weekday lunch host at the popular seafood restaurant? You thought he might be home enjoying his golden years? "You can only read so many books and watch so much 'Law & Order,' " Krupin explained his return, 21/2 years ago, to the industry that made him almost as famous as the VIPs he welcomed and ribbed, beginning in 1968 when he was maitre d' at Duke Zeibert's restaurant and later at Mel Krupin's. (The restaurateur dubbed his menu of matzoh ball soup, steaks and pickles on every table "Judo-American.")

We wanted to know how the dining public has changed since the Brooklyn native got into the business. "They're too casual," Krupin said, noting that jackets were mandatory at the late Duke Zeibert's. The restaurant kept a few coats on hand for men who didn't have them -- and resorted to borrowing waiters' jackets when the extras ran out.

Krupin is the king of one-liners. Once, when a woman asked him for a table, he shot back with this zinger: "You want a TABLE? Try Marlo Furniture. You want lunch, stay here."

GET HAPPY WITH HOPS: "When you think about pizza," asks Bob Resor, a manager at Pizzeria Paradiso (3282 M St. NW; 202-337-1245), "what goes with pizza? Beer!" And so it is that the Georgetown branch of the Dupont Circle original began whipping up cocktails using beer for its new happy hour, which takes place weekdays from 4 to 6:30 p.m. "Jailhouse Sangria" swirls Jever pilsener with tequila and lime juice while "R & R" blends rum with Rogue's Dead Guy ale for an R-rated punch. They are among a half-dozen specialty drinks imbibers can ask for, along with a pie, in the cheerful, brick-and-window-wrapped dining room. At -- gulp! -- $10 to $15.95 each, the cocktails are priced for the expense-account set. The real deal unfolds with the food: Paradiso's signature wood-fired pizzas cost a mere $4.25 (for half an eight-inch pie) during happy hour, and there are several flavors from which to choose; we gravitate toward the "Atomica," scattered with hot peppers and salami slices. The promotion also includes an antipasto plate for $6.95. Enough for two to share, it features a choice of three salads, cured meats and cheeses from a roster of six.

Mel Krupin, multitasking in 1988.