Analysts are calling on Sun Microsystems to make its NetBeans open-source integrated development environ- ment (IDE) work with the Eclipse open-source IDE, in order to head off the challenge from Microsoft's dot-Net.

Eclipse started life as an IBM initiative but last year IBM handed over control to the independent Eclipse Foundation. Sun contributed NetBeans to the open source community in June 2000, and IBM made Eclipse open source a year later.

Sun said that there have been two million downloads of the NetBeans IDE. But Eclipse - which supports development in other languages in addition to Java - has gained even greater traction among Java developers.

Sun has so far been cool to the idea of making NetBeans and Eclipse work together. But Jeff Jackson, sun vice-president of engineering for the J2EE Platform, last week said the company had not ruled out joining with Eclipse in the future - though other executives seemed to suggest that it would not happen. At the JavaOne developer conference in San Francisco, Sun president Jonathan Schwartz responded to a question about Sun's lack of Eclipse support by saying, "Have you seen the Eclipse licence? It is very restrictive."

Sun chairman and chief executive Scott McNealy commented, "IBM has been very participative in J2EE [Java 2 Enterprise Edition]. [But] they wish they were the [Java] stewards and had invented it. It is a sales advantage and so they would like to wrest away stewardship."

However, Jonathan Eunice, president of analyst Illuminata, said, "Independent software vendors go to where there's something available. Talk to them about how they're using [Eclipse]. It isn't overly restrictive." And Gary Barnett, principal consultant at analyst Ovum, warned that Sun and IBM could be playing into the hands of Microsoft. "The problem with the Java community is that they're always fighting among themselves. It's important. The more they argue the greater the advantage Microsoft dot-Net gets. It's still possible Java could make itself irrelevant," he said.

Barnett also backed Eclipse for another reason. "Real large customers develop simultaneously in multiple languages and having common tools frameworks and functions has got to be good. Support for Eclipse would be a good thing for NetBeans. It shouldn't be too difficult to do, either technically or politically."

James Governor of analyst firm RedMonk said Sun should join Eclipse to benefit from the huge momentum behind it. "How is Sun going to persuade users to replace their existing SAP [Eclipse] frameworks with NetBeans?" he added.

Last year talks between the two camps broke down amid reports that the Eclipse Foundation had demanded that Sun should abandon NetBeans. Sun has since donated 350,000 lines of code to beef up the latest version of NetBeans.

However, there are now signs both parties see a need to co-operate. Eclipse version 3.0 - announced ahead of the JavaOne conference - for the first time allows access to NetBeans' Swing components used for developing graphical user interfaces.

The Eclipse Foundation had previously rejected Swing tools and produced its own Standard Widget Toolkit.

The Sun-backed Java Tools Community (JTC), formed in January to speed development of Java standards, may also assist NetBeans adoption.

The JTC includes heavyweight Java companies BEA, Oracle, SAP, Compuware, Borland and SAS, most of which are also Eclipse Foundation members who may want to see the rift healed. But, significantly, IBM has not joined the JTC.