Office update v. Microsoft update

[H+S IT]

I have an administrative install of Office XP Pro. I have patched this
install with the most up to date patches. When I do a new install, or update
an existing installation, from the administrative install point, Microsoft
Update (update.microsoft.com) still says I need the last two patch sets I
installed. When I run the Office Update
(office.microsoft.com/officeupdate/), it says my Office products are
up-to-date! When I click on "Show already installed Office updates", from
the Office Update site, it lists these patches as being installed.
What would cause Microsoft Update to not see that these patches are
installed, where Office Update see that they are.
FYI, the patches Micrsoft Update says are not installed are the following:
Security Update for Word 2002 (KB917335)
Security Update for PowerPoint 2002 (KB916519)
Security Update for SharePoint Team Services (KB911701)
Security Update for Outlook 2002 (KB905649)
Update for Office XP (KB913471)
Security Update for PowerPoint 2002 (KB905758)
Security Update for Excel 2002 (KB905755)

Thanks for any information you can provide on this issue.