Netscape's army of open-source browser developers prepares for battle on a new front: Web-based applications. The key weapon in the Mozilla.org arsenal: XML-based User Interface Language. Its war cry: 'Fight Microsoft.Net world domination!' Netscape's army of open-source programmers may not have turned the tide in the browser wars, but that hasn't stopped some followers from moving on to the next front in the battle for control of the Internet. Mozilla.org, founded by Netscape to develop its browser in an open-source environment, has long touted its technology as a potential foundation for building applications such as word processors or spreadsheets for the Web -- an area Microsoft and others covet. One of these technologies, dubbed XUL (XML-based User Interface Language, pronounced "zool"), launched with Netscape's promise that it could spur a "programming revolution" beyond the realm of browser development. These efforts are getting a boost from a new CollabNet-backed site called MozDev.org. Since September, it has offered independent developers the infrastructure to work on Mozilla-based application projects and stimulated those contributions into becoming one of the hottest new areas of software development. Comeback claims from the Netscape camp face enormous scepticism, given that Mozilla is still labouring to release its version 1.0 browser, and work on non-browser applications has also been slow to take off. Doubts persist that the open-source programming model is an efficient way to create viable commercial products. Scepticism aside, the drive to create more powerful Web-based applications puts MozDev and Mozilla in line with an ever-expanding array of competitors looking toward a future in which such applications, located on Web servers, displace the current model of PC-based computing. Microsoft has placed great emphasis on its Microsoft.Net initiative to move its bread-and-butter PC-based productivity applications to the Web. Oracle has countered with its own software release. And some expect Sun to throw its hat into the ring with a project code-named Brazil. Mozilla's most ambitious members hope that the open-source projects under way at MozDev.org will act as a thorn in the side of the software giants' plans. The Mozilla-based Web application "has the potential to be the most powerful side of Mozilla yet (and Microsoft's worst nightmare)," reads the launch site of MozOffice, an open-source productivity suite hosted by MozDev.org. "Fight the Microsoft.Net world-domination strategy!" Whatever the worth of Mozilla technologies to create user interfaces on the Web, analysts questioned the potential for open-source developers to create software sufficiently secure for commercial Web applications. "The difficulty we have in trying to move major Web development projects to an open-source environment is that these are projects that companies typically are betting their businesses on, that require a great deal of reliability and security," said Rob Enderle, analyst with the Giga Information Group. "Open source hasn't lent itself to the security side of things. Too many people know how it works, so that the opportunity for somebody to know how to get around the security platform looks to be significantly enhanced." Between Microsoft and the open-source projects sits a host of well-funded start-ups seeking to develop or host these kinds of applications. Some high-profile ventures, such as Redmond, Wash.-based Crossgain and OpenDesign -- both backed and founded by Microsoft alumni -- describe their as-yet-unreleased projects much in the same way that Mozilla views its technology, as "platforms" for Web-based application development. Web-based delivery of core applications raises a host of problems that have limited widespread development and adoption. As a result, most PC software today far outstrips Web-based rivals in both popularity and functionality. But Mozilla and MozDev say XUL could possibly step up the potency and popularity of applications on the Web. Part of XUL's appeal is that it lets developers code their Web application interfaces using a comparatively simple and cross-platform Web language, rather than computer languages tailored to specific operating systems. "With Mozilla technology, it's increasingly possible for people to create applications without being C++ or C programmers," said Mitchell Baker, the Mozilla.org representative whose title is chief lizard wrangler, after Mozilla's reptilian mascot. "Now the barrier to designing a (user interface) is much lower. It's the same set of knowledge required to lay out a Web page. And so that brings the ability to design and modify user interfaces to a much broader range of people." Additional advantages of XUL are manifold, its backers say. Because the browsing engine renders applications written in XUL, one version will work on any operating system supported by the browser. And because XUL is simpler than standard computer programming languages, the bar of computing expertise will drop for application developers. "The Mozilla framework is flexible enough so can you create almost anything using the new Mozilla technologies, primarily XUL," said David Boswell, CollabNet project manager. "XUL allows you to change the browser interface so much that it's no longer a browser. The application is now the Web page." Indeed, the pace of XUL- and Mozilla-based application development has spiked since the launch of MozDev in September. The site boasts more than two dozen applications under development and adds one or two every week. Early activity in the area of Mozilla-based application development -- such as the Netscape-sponsored project to build instant messaging into the browser -- has earned the group harsh criticism from those who wanted it to focus on putting out a feature-complete, stable browser that could provide credible competition to Microsoft in the increasingly lopsided browser war. "There has been a lot of discussion over whether Mozilla should even have mail and news at all or just the rendering engine that one thinks of as the browser," said Mozilla.org's Baker. "With MozDev we can say to developers of applications, 'That's not really the core of what we're doing. Go to MozDev.org.'" In addition to shielding Mozilla.org from critics impatient with extracurricular distractions, MozDev serves as a showcase where sponsor CollabNet demonstrates its SourceCast open-source development tools. Developers can take advantage of those tools for entering bugs, keeping track of version numbers and the like. Projects under way at MozDev.org include everything from games to MozOffice, the effort to merge Sun's open-source office suite, called StarOffice, with Mozilla. Boswell agreed that the MozOffice project warranted a comparison with Microsoft's .Net ambitions. "This obviously is similar to .Net in a way because it's providing full-fledged applications on the Web," Boswell said. "One thing that .Net would do is create a Web-delivered version of Microsoft Word. MozOffice is the same thing, creating the Mozilla-based version of it. You could have all the features and functionality that a .Net version of Office would have. But since this is open source, there'd be no monthly charge." Ari Bixhorn, product manager for Microsoft's Visual Basic programming language, countered: "XUL appears to be not much more than an alternative markup language such as HTML. It looks like it's doing a lot of what an ActiveX control would do: downloading an applet and running that as a rich-client application rather than (creating) a true Web application like we have at .Net. Also, it's a single, non-standardised language that people would have to learn, whereas with .Net you can choose from a number of languages." Bixhorn also touted Microsoft's C# (pronounced "C-sharp"), a simplified version of C and C++ designed for applications on the Web. "With Microsoft.Net, we have made it much easier to create Web applications using C#, a first-class, object-oriented .Net language that allows C and C++ programmers to easily create Web or Windows applications," Bixhorn said. "With all of our languages and with Visual Studio.Net, creating an application is as easy as dragging and dropping controls onto a form and then making that form functional using a language that you already know, such as VisualBasic or COBOL." Other projects under way at MozDev include Aphrodite, a Mozilla-based browser with a crash-recovery system; Fabula, a learning tool for minor Romance languages; and Jabberzilla, a cross-platform instant messenger. Building on Mozilla Those developing their applications on MozDev.org praised the site for providing an environment outside of Mozilla.org for them to work. "I think having a smaller site like MozDev.org that is independent of the 'monster' Mozilla.org site is very important for the future of 'Mozilla as a platform,'" said Ramalingam Saravanan, author of the MozDev-hosted Protozilla project. "At the moment, Mozilla.org is focused on getting an efficient browser completed, and many of the activities at MozDev could be considered a distraction in that context." MozDev is not the only site on the Web catering to open-source development projects. Saravanan first considered SourceForge.net, a site spun off by VA Linux (Nasdaq: LNUX) that boasts a whopping 15,029 hosted projects and 115,153 registered consumers. "They're OK, but they are rather big and lack the focus that MozDev provides -- a site exclusively devoted to a small but growing group of Mozilla enthusiasts," Saravanan said. The success of projects hatched under MozDev.org could give Mozilla a badly needed shot in the arm as the project falters in its race to catch Microsoft's Internet Explorer browser. Netscape 6.0, based on a November snapshot of the Mozilla codebase, was widely judged to be not ready for prime time. Mozilla's own Version 1.0 is not scheduled for release until next quarter. But with browser development in general reaching an advanced stage of maturity and attention turning to Web-based applications, the success of MozDev projects and the acceptance of XUL as the basis for such applications could have the potential to make Mozilla's technologies newly relevant. "MozDev.org and the projects that are being developed there are a key part of the long-term view for Mozilla," Baker said. "We've always known that Mozilla would be a platform and that people would find uses for it that we've never dreamed of. The real usefulness of the technology and what it can develop into will come about through the serendipity of smart people with creative ideas working together." Find out how the open-source movement is revolutionising the high-tech world at the Linux Lounge. Have your say instantly, and see what others have said. Click on the TalkBack button and go to the ZDNet news forum. Let the editors know what you think in the Mailroom. And read other letters.