NEW YORK - In another sign of the grim holiday season, KB Toys filed for bankruptcy protection for the second time in four years yesterday and plans to begin going-out-of business sales at its stores immediately.

That a toy retailer filed for bankruptcy just before Christmas shows how bleak things have become, since such stores make up to half of their sales during the holidays. But analysts expect toy sales this holiday season to be flat or down slightly from last year's total of $10.4 billion.

KB Toys joins a growing list of retailers in bankruptcy, including Mervyns LLC, The Sharper Image, Steve & Barry's, Linens 'N Things and Circuit City Stores Inc. *