Microsoft has released a new version (4.01) of its IntelliPoint drivers. This new version works with every Microsoft mice and is fully compatible with Windows XP. IntelliPoint software gives your Microsoft® mouse full functionality and lets you customize the mouse to fit your needs.
News source: Microsoft Mouse Home Page
Download: IntelliPoint 4.01 W2K/ XP
Download: IntelliPoint 4.01 Win 9x/ Me