Supported by a bevy of on- and offline figures from the music world, the Recording Industry Association of America asked a federal judge on Monday for an injunction against the popular Napster MP3-trading software, the RIAA said in a statement.

Michael Robertson, CEO of downloadable-music Web site MP3.com; Bob Kohn, chairman of MP3 retailer EMusic.com; and Mike Stoller, one-half of the Leiber-Stoller songwriting team ("Hound Dog," "Stand By Me"), were among those who gave statements in support of the motion.

The RIAA sued Napster Inc. in December, claiming the program facilitates music piracy by allowing users to trade near-CD-quality MP3 music files without permission from the copyright holder. Last month a judge rejected Napster's motion to dismiss the suit on the grounds that as an Internet service provider the company is protected from copyright claims.

Napster has also been sued on similar infringement allegations by hard-rockers Metallica and rapper/producer Dr. Dre.