Microsoft has released a patch that updates Riprep.exe to allow the creation/deployment of Windows XP images across a Windows 2000 RIS server.

Download Windows 2000 Patch: Win2k RIPrep needs to support Win2k SRV, ADS and XP client images for Windows 2000

System Requirements

Microsoft Windows 2000 Professional
Microsoft Windows 2000 Server
Microsoft Windows 2000 Advanced Server