Yahoo's messenger service is enormously popular

Rival internet company AOL, which is investing in a separate music service, Musicnet, dropped a feature from its messaging service last year which allowed users to search for music files.

The company was concerned that copyrighted music files were being swapped by users.

Rock band Garbage has signed up as one of Yahoo's partners and its single Androgyny will be available for instant message users to share.

Yahoo has said it hopes to sign up more music partners over time to increase the availability of music to users.

Other content available to Yahoo users includes comic strips from Peanuts, previews of new games from Nintendo and an animated fighting game.

'Innovative'

More than five billion instant messages were sent using Yahoo in September, up 115% on last year, according to internet tracking company Media Matrix.

Lisa Pollock, director of messaging products at Yahoo, said: "We are keenly focused on our users' needs and will continue to introduce more innovative features."

The battle for supremacy in the instant messaging market is extremely fierce with AOL and Microsoft offering rival systems.