IBM thinks it has an answer for big enterprises fed up with the complexity of supporting enterprise applications running across hundreds, or even thousands, of small servers--run everything off a single mainframe.

For the past several months, the computing and services giant has been encouraging smaller, niche-specific independent software vendors to port their software to the company's zSeries mainframe, which runs Linux on top of its native OS to create literally thousands of independently functioning "virtual machines." The company took the strategy a step further Thursday when it said software vendor SAP will make its mySAP enterprise suite available for Linux on IBM zSeries mainframes. The software is slated to ship in the second quarter.

MySAP is the first large-scale enterprise app to hit the Linux platform, and observers say the move should help IBM realize two key elements of its growth strategy. The company is seeking broad developer support for Linux to compete more effectively against Sun Microsystems in the Unix market; at the same time, it's looking to boost mainframe sales by positioning the so-called Big Iron boxes as cost-effective, easily managed alternatives to unwieldy server clusters. "This adds some flexibility to the mainframe, which as a platform has been in decline for some time," says Technology Business Research analyst Bob Sutherland.

IBM officials say more such deals are on the way. "This is the tip of the iceberg," says Dan Powers, the company's director of early-stage Internet technologies. Powers says there is a good possibility that Siebel will make its CRM apps available for Linux on the zSeries, adding that, "We're also looking to bring supply-chain management to this environment." IBM shares were $89.10 at the close of trading, down from $89.12.