IBM is bringing more of its WebSphere middleware suite to the mainframe, part of ongoing investments to keep the venerable server modern and cost-effective.

The company on Monday said more components of its WebSphere line of Java server software, including its portal and business integration server, will run on the mainframe operating system later this year.

IBM is also enhancing its program with third-party application providers with more technical and sales assistance, in an effort to get those partners to convert their applications to run on the mainframe, said Steve Mills, senior vice president and general manager of IBM's software group.

Mainframes were once written off as too pricey and they still to appeal primarily to large corporations. But IBM, with a significant financial interest in mainframes, continues to invest in the platform, Mills said.

"We have a big franchise, so it's important that customers have a road map," Mills said. "If you don't keep things modern and moving, the buying pubic will perceive this is as an old system unable to do what they want to do."

IBM also announced a tool that automatically generates Cobol code. The Rational-branded product is meant to simplify the task of writing mainframe applications for programmers familiar with Java and Linux, Mills said.

"You don't have to have unique mainframe skills," he said. "We're opening up the aperture to more programmers with more diverse skills."