Sun Microsystems said Wednesday that it will offer all its core software products as open-source, making all of its middleware, management and Java development tools free to use. The move follows Sun's decision last year to offer Solaris as open-source and is aimed at developers.

The decision doesn't change pricing for corporate users, who will still have to pay for service and support for these products if they want them, said Sun officials. Corporate users can use the company's Java Enterprise System (JES) middleware stack for free, but they won't have support or service. Sun believes corporate users won't use the products unless they have service and support, but in-house developers, interested in trying out the products, will find the no-charge aspect appealing, Sun officials said.

The move is designed to get the company's software before a group it sees as a major influencer in corporate IT -- the development community.

Sun President Jonathan Schwartz was blunt during a teleconference at which he talked up the company's strategy: "These are folks that don't necessarily have access to a lot of money, but they certainly have the ability to move the landscape. And they are certainly a community that is absolutely core to [Sun].

"Volume wins in the marketplace - especially the marketplace for technology," he said.

Sun will make open-source JES, which includes an application platform, identity management, and an integration and communications suite, among other tools; its N1 Management Software, including its grid engine; all its development tools for C, C++ and Java; and its thin-client software for its SunRay System.

Sun now offers its JES system, for instance, at subscription pricing of US$140 per employee, per year for the entire suite. That price, which covers service and support, won't change, and Sun expects corporate users will continue to use this service and support. But Sun will also bundle and integrate the entire package, including its Solaris operating system and development tools, under one umbrella product, the Solaris Enterprise System. Pricing for that wasn't released today.

Sun will make the products open-source over the next year, in part because some of the products are using code from recently acquired companies such as Tarantella and SeeBeyond Technology.