BEA has risked the ire of Sun by saying it would like to see Java made open source on the same day that Sun CEO Scott McNealy ruled it out, and while at Sun's own JavaOne conference.

"We'd like to go on the record publicly in favour of open-sourcing J2SE and we've been working behind the scenes on this," said Scott Dietzen, BEA's chief technology officer, during a speech at the JavaOne show.

J2SE, or Java 2 Standard Edition, is considered the desktop version of Java, although many vendors also base their Java application servers on it. J2SE version 5, codenamed Project Tiger, was announced this week.

Making Java open source would lead to more innovation around the Java language and fits with the business models of Java vendors, Dietzen said. The vendors don't profit from core components like the Java virtual machine. "Allow everyone to innovate freely, but if you want to ship with the Java brand you've got to be compatible. That way you as developers know you'll be working with compatible Java code," he espoused. He also called for more openness in compatibility testing kits.

IBM sparked the furore over open-source Java in February when it urged Sun to make the move in a public letter. IBM argued that it would help to expand Java's reach and boost innovation. Sun said it was open to the idea but was worried about forking and said the move would be complex.

Yesterday though, Sun's CEO Scott McNealy appeared to give the whole idea the thumbs down saying: "Somebody's got to be in charge or nobody is." And that somebody is, of course, the Great McNealy.

A panel will nevertheless discuss the matter at the conference today, with top engineers from Sun and IBM joined by Stanford University Law Professor Lawrence Lessig, and IT publisher Tim O'Reilly. Dietzen's comments sparked applause from attendees in the auditorium, although some developers here have said it makes little difference to them if Java becomes open source or not.

BEA, along with IBM, makes one of the two most widely used Java application servers.