DINNER THEATERS come in all kinds and variations nowadays. Even the Kennedy Center has its version.

For the run of "Satchmo: America's Musical Legend" through September 5, the Center's offering a dinner and theater package for $49.95 Sunday through Thursday, $52.25 Friday and Saturday. Prices include a theater seat and a full-course dinner in the Roof Terrace (drinks, tax and tip extra).

What's more, the dinner's in tune with the show: Cajun, prepared under the supervision of a New Orleans chef lent by Copeland's, the Louisiana restaurant chain that recently opened an outpost in Alexandria.

The Kennedy Center restaurants have coordinated shows with a food theme before -- a Greek menu for "Zorba" and a Transylvanian one for "Dracula," for instance -- but this is the first time they've worked with another restaurant. "I really wanted very authentic Cajun food, and I didn't just want to get it out of cookbooks," explained Restaurant Associates veep Arnie Malin.

What that means is a theater-package menu of Cajun Gumbo Ya Ya or Maw Maw's Jambalaya to start; Roast Cajun Duck, Catfish Acadiana, Blackened Chicken Little or Smoked Pork Tenders as main dishes, all with red beans and rice plus collard greens; and dessert of Wild Bread Pudding or ice cream.

The regular Roof Terrace menu will also be available, plus a few a la carte items such as Huey's Andouille, Blackened Prime Rib, Fresh Fish Copeland and Bananas Foster. The Hors D'Oeuverie will also have Cajun offerings, and the cafeteria will serve the jambalaya and bread pudding.

RESTON, THEIR LAURELS --

If you hadn't until now considered moving to Reston, here's a powerful incentive. Tiffin, a brand-new catering company, delivers some of the most delightful box lunches I've ever seen, but only to the Reston-Tysons Corner area. While Tiffin actually does more than lunches -- breakfasts, dinners, picnics and parties -- the box lunches are the mainstay. They must be ordered before 2 p.m. the previous day, and cost $6.75 plus tax.

For that you get a choice of 10 lunches, with homemade breads and such centerpieces as oriental chicken salad of big juicy chunks tossed with bright crisp broccoli, snow peas, water chestnuts and almonds; or tangy marinated roast beef in a Mexican beef salad; or a salad assortment including Italian beans and peppers, orange broccoli with cashews and potato salad made with Pommery mustard.

Every day there's a special such as three-color ravioli salad with prosciutto, pecans and fresh herbs. Lunches include salad -- the best is a bright and refreshing dilled carrot slaw -- plus beverage (fruit juce, mineral water or sodas) and dessert (homebaked cookies, fresh or dried fruit or Gummy Bears). My only disappointment was damp turkey breast that tasted commercially packaged; otherwise, the quality was outstanding. Herbs are fresh, fruit is ripe, and the baked goods are fine. Their number's 689-3308.

NAME THAT DINER --

Jeff Gildenhorn keeps trying to fulfill our wishes. First it was a seafood restaurant -- The Fishery and its adjacent market. Then, in hopes of satisfying our yearning for a real pizza, Rossini's and its adjacent market. Now he's planning to feed our nostalgia, with a real diner at Connecticut and Morrison NW.

And I mean a real diner. Gildenhorn's having a replica of a 1945 diner built in steel, mosaic tile and Formica, in Newark, where they still know about such things. While the diner isn't due until the end of the year and doesn't yet have a name (contenders: Connecticut Avenue Diner or Johnny Valentine's), Gildenhorn has already decided that it will be open 24 hours a day, the jukebox will be stocked with '50s music, and prices will be in the range of $5.50 for a blue-plate special.

As for the bill of fare, he's poring over those of diners all over the country and has a strong leaning towards meatloaf and mashed potatoes, homemade pies, milkshakes, hot dogs from Baltimore, and breakfast served round the clock.

Gildenhorn's already laying in a supply of Cokes in deposit bottles.