CUPERTINO, Calif. – Apple Computer Inc. unveiled software today to help owners of its new Intel-based Macs run Microsoft Corp.'s rival Windows XP operating system, despite the computer maker's insistence it won't assist such efforts.

Apple's new "Boot Camp" software, a "beta" test version available as a free download, lets computer users with a Windows XP installation disk load that system on the Mac.

Apple shares rose more than 6 percent in morning trading.

When Apple introduced its first computer based on Intel Corp. chips in January, the company said it had no intention of selling or supporting Windows on its machines, though it has not done anything to preclude people from doing it themselves.

Apple said today that stance remains true, yet the new software will ease Windows installation "by providing a simple graphical step-by-step assistant application."

"Apple has no desire or plan to sell or support Windows, but many customers have expressed their interest to run Windows on Apple's superior hardware now that we use Intel processors," Philip Schiller, senior vice president of worldwide product marketing, said in a statement.

Apple turned to Intel chips, the same ones used to power most PCs using Windows, after saying its previous suppliers, IBM Corp. and Motorola Corp.'s spinoff Freescale Semiconductor Inc., couldn't meet Apple's needs for faster, more energy-efficient chips.

But the Intel-based Macs continued to run Apple's own proprietary operating system.

Because Windows is much more dominant, Mac users don't have access to many software programs written only for Windows. The switch to Intel chips lets users load Windows onto a Mac computer, without the need for emulation software that slows performance. But until today, the user needed some technical expertise to pull it off.

The Boot Camp software makes it easier to install Windows and lets users run either Mac OS X or Windows when they restart their computer.

A final version of Boot Camp will be available as a feature in the upcoming Mac OS X version 10.5, code-named "Leopard."

Apple shares gained $3.79, or 6.2 percent, to $64.96 in morning trading on the Nasdaq Stock Market, while Microsoft shares rose 21 cents to $27.85 and shares of Intel rose 2 cents to $19.32.