Tomorrow, Microsoft will release Windows XP Service Pack 3, the first major update to the OS since 2004. Apple has released a required Boot Camp 2.1 update for SP3, and VMware has released an SP3 update for Fusion. Service Pack 3 will be available to users via Windows Update.

Windows XP SP3 includes a collection of hotfixes and stand-alone patches plus some networking security features found in Windows Vista and Windows Server 2008. For instance, it includes Network Access Protection (NAP), which adds server-enforced policies that can prevent a computer from joining a network if certain "system health" requirements are not met. Windows XP SP3 does not include Windows Internet Explorer 7, which comes with Vista. (For more about what's in Windows XP Service Pack 3, click here.)

Apple released Boot Camp 2.1 last week to support Windows XP Service Pack 3 on Intel Macs. The update is required to run SP3, and must be installed before updating Windows XP to SP3 on a Mac. Apple said that the update also "improves compatibility" with Microsoft Windows Vista, but did not elaborate.

VMware also issued an update to its Fusion virtualization environment for Intel Macs. Fusion 1.1.2 adds support for Windows XP SP3 installed in a Boot Camp partition. The update also fixes some other bugs and adds enhancements. (Click here for more on Fusion 1.1.2.)

Service Pack 3 comes only two months before Microsoft's stated June 30 retirement of Windows XP. On Friday, however, Dell Computer said that it would continue to ship computers loaded with Windows XP after June 30.

If you've tried running Windows XP SP3 on your Mac with Boot Camp, VMware, or Parallels how it worked for you.