StreamCast Networks' Morpheus--a file-swapping service that many have said would be impossible for courts to shut downâ€"-shut out most of its users today, citing "technical problems."

Computer users trying to log on to the service were greeted with a message telling them to upgrade their software to connect, although no newer version of the software was available. The outage immediately sparked a huge increase in traffic on alternative file-swapping services, such as Gnutella.

In a statement, StreamCast blamed Kazaa, another file-swapping company that had provided the basic software that served as the foundation of the Morpheus program. Kazaa, along with fellow software licensee Grokster, have recently issued upgraded their software, while StreamCast has not.

"Unfortunately, Kazaa's recent upgrade has made Kazaa's and Grokster's new versions incompatible with Morpheus," the company said in its statement. "As a result, we are accelerating the release of our new Morpheus software and within days expect Morpheus users to enjoy the Morpheus Preview Edition."

That new software, the company said, would operate using an "open protocol" network. That typically means that different software companies can write pieces of software that talk to each other. The network used by Kazaa, Grokster and until now by Morpheus, is a "closed protocol" network in which each company has to license the software from the owners.

StreamCast has previously said it would add support for the open-source Gnutella network in future versions of its software. Streamcast executives could not immediately be reached to provide details on the new software.

A Streamcast move entirely to Gnutella or another "open protocol" network would send a shock wave through the file-swapping community.

Together, Kazaa, Morpheus and Grokster had created a joint network that neared or even exceeded the size of Napster at its peak. Anyone using any of the three programs could search other users' computers.

The Morpheus software appeared to be the most popular of the three, however. According to Download.com, which keeps a count of people downloading the software, Morpheus has been downloaded more than 51 million times.

Kazaa has seen more than 37 million downloads, while Grokster has seen just over 1 million, according to the site. Download.com is a division of CNET Networks, the publisher of News.com.

Moving Morpheus users to a Gnutella-based network could also prove technically difficult. The open-source Gnutella technology has had difficulties with large numbers of user in the past, and has stumbled when large influxes of users overloaded the network. Some of those problems have been addressed in more modern versions of Gnutella software.

Gnutella software was one benefit of the Morpheus outage, however. According to statistics kept by Limewire, a distributor of Gnutella software, the number of people using Gnutella at the same time jumped by well over 50 percent, to more than 100,000 people, by the end of the day. StreamCast, along with Kazaa and Grokster, is being sued in Los Angeles federal court by the big record labels and movie studios, which contend the services are contributing to widespread copyright infringement. The two sides are scheduled to meet in court March 4.

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