Research In Motion Ltd. said it is recalling about 1,000 BlackBerry PlayBook tablets a month after the device went on sale, because of a glitch in the operating system that may make the software not load properly.

Most of the affected devices are still with distributors and not in the hands of customers, the Waterloo, Ontario-based company said in an e-mailed statement. RIM will replace affected devices and said customers with faulty software should contact the company.

RIM fell 24 cents to $43 in early trading after closing at $43.24 in Nasdaq Stock Market trading on May 13. The stock has lost 26 percent this year.