OneNote 2003 Service Pack 1
OneNote 2003 Service Pack 1 provides the latest updates to Microsoft Office OneNote 2003
http://www.microsoft.com/downloads/details.aspx?FamilyID=07408348-26C9-43BB-9E7E-6151CF15D415&displaylang=en
OneNote 2003 Service Pack 1 (SP1) contains new features and significant security enhancements, in addition to stability and performance improvements.
You can get specific information about this update in the Microsoft Knowledge Base article (842774): Description of OneNote 2003 Service Pack 1.