Microsoft and Sun Microsystems have boosted their respective development environments with a .Net development tool and the naming of Java 2 Platform Enterprise Edition (J2EE) certified vendors.

Launched yesterday, Visual Studio for Applications is a tool for Microsoft's .Net framework that enables developers to customise existing web applications to fit corporate policies.

Robert Green, Microsoft's Visual Studio lead product manager said: "There is nothing equivalent for customising web applications." He added that users can use Visual Basic's event-driven model to tailor core business logic.

The tool is expected to go into beta in the spring and ship in the second half of the year to coincide with the availability of Visual Studio .Net. It will initially support web applications written in Visual Basic with support for third-party .Net software expected in a later release.

Meanwhile, Sun said that eight J2EE licensees have passed the environment's compatibility test and are now certified to ship J2EE-supported products.

The vendors are BEA Systems, iPlanet, Sybase, Art Technology Group, Bluestone Software, Borland, Iona Technologies and SilverStream. These are the first certified licensees out of a total of 25. J2EE is a version of Java designed to handle tasks such as ecommerce running on back-end servers.

Compatibility verifies that J2EE-based configurations work across a heterogeneous network, and certification allows for faster time to market with J2EE technology. It also makes it possible for components and applications to run on third-party application servers.

Tracy Corbo, an analyst with consultants the Hurwitz Group, said: "This announcement demonstrates the success of Java technology on the server platform and the demand for more open technology standards. Increased compatibility across multiple application servers helps to simplify cross-platform development and deployment tasks."

Sun also revealed additional details about version 1.3 of J2EE that include interoperability, standards-based data interchange and the ability to integrate best-of-breed software. Also new is simplified connectivity to existing applications with support for XML integration.