The service will carry the Napster brand and combine elements of the digital music firm's PC offering and Ericsson's existing personalised music service for mobile operators.
It will support coordinated wireless and PC downloading of digital music on both subscription and à la carte tariffs.
Under the terms of the agreement Napster's brand, catalogue, label relationships, programming, PC and portable offerings will be combined with Ericsson's operator relationships, wireless development, integration, hosting, deployment, support and IPX charging systems.
The service will allow mobile operators to sell ring-tones, master tones, images, wallpaper and video content.
According to Ericsson and Napster the service works with current handset models and networks but can also accommodate next-generation technology for newer handsets on higher-speed networks.
It is designed to work on mobile phones from all major manufacturers that support content protected by digital rights management.
Chris Gorog, Napster's chairman and chief executive, said that the firm had partnered with Ericsson because of its wireless and telecoms experience, and its "exceptional client base".
The main benefit for Ericsson, according to Carl-Henric Svanberg, president and chief executive at Ericsson, is the strength of Napster's brand and its extensive music catalogue.
The service is scheduled to go live in Europe over the next 12 months and will be offered initially to operators in selected markets in Europe, Asia, Latin America and North America.
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