The vendor said that it is handling around 11,000 downloads a day since it open-sourced Solaris in January.
"The interest in Solaris 10 is exceptional," said Tom Goguen, vice president of Sun's Operating Platforms Group. "By open-sourcing Solaris and our Java EE applications server, Sun is enabling a new wave of innovation in the industry."
Solaris 10 includes more than 180 of the most popular free and open source software packages such as the Sun Java Desktop System, GNU utilities, the Perl and Python programming languages and the Sun Java System Application Server, an open source Java EE certified application server based on Sun's GlassFish project.
The news came after the company's financial results showed a profitable fourth quarter and a loss of $11m this year, compared to a $388m loss last year.
This year's figures include a $1.6bn payout from Microsoft to settle outstanding legal issues.
"It always feels good to make money," said Scott McNealy, Sun's chief executive. "We spent the past year getting in shape and succeeding on a lot of fronts, and setting the company up for a really successful 2006."
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