Columbia Catering is back in business today, after being padlocked for five days by the Internal Revenue Service.

Steven R. Ray and Barbara Chow, who left a $2,000 deposit with Columbia for an elegant wedding reception on April 6, have been assured preparations are under way.

A lucky charitable organization in Rockville will soon have 2,000 of Secretary of State George Shultz's favorite chocolate lace cookies, made before the closing and now "edible, but not quite up to our freshness standard," as Columbia president William Seltzer said.

And the caterers are out serving a luncheon for a new customer today.

The fate of Columbia and its staff had been in doubt. Last Thursday the IRS padlocked Columbia, charging the firm owed back withholding taxes. Cookies, canape's, boxes of strawberries and other perishables were to be auctioned off by the IRS at 11 a.m. Tuesday. In the last six minutes, Columbia filed for bankruptcy and the IRS called off the auction. The IRS handed back the keys yesterday afternoon when an agreement was reached on an "orderly way to pay back and future taxes."

Seltzer, who has often catered IRS receptions, said he didn't have a party scheduled for the IRS this week.