Sun said Thursday that it would alter its licensing terms in order to make Java easier to bundle with open source operating systems. The announcement is expected to come at the JavaOne conference later this month.

The changes specifically target the Java Runtime Environment, which is needed to run Java programs on the computer. Sun will allow developers of operating systems such as Linux, FreeBSD and OpenSolaris to include the JRE as part of the OS, without licensing restrictions.

Developers have repeatedly called on Sun to open source Java, as they said such a move would help to spur development on the platform. The company has resisted such pressure, but it has taken steps to make it easier for developers to gain access to portions of the code.

As well as opening up the licensing terms, Sun is also expected to make an announcement regarding Java Platform Enterprise Edition 5. The company plans to offer a software development kit that aims to make Java server applications programming easier, it said in a conference call with members of the press.

Companies such as BEA Systems, Oracle, JBoss and SAP all say they are already developing using the SDK and would have products available over the next 18 months.

Java EE 5 adds several enhancements over previous versions. It supports Enterprise Java Beans 3.0 standard, as well as built in support for AJAX.

"The new ease-of-development features in Java EE 5 are designed to allow developers to get more accomplished in less time and to reduce the complexity of the code they produce," Sun distinguished engineer Bill Shannon said in a statement.