Service release updates

[Tully]

I am attempting to update an administrative installation
point using the Microsoft Office Resources Kit. For
example to update for Service Pack 1 I used the command:
msiexec /p <path of administrative installation
point>\MAINSP1_Admin.msp /a <path of administrative
installation point>\PRO.msi SHORTFILENAMES=TRUE /qb /L*
<path of administrative installation point>\patch1.log
This worked great; as did the msp file for Service Pack
2. I am trying to apply eight service releases published
since SP2 using the method above. Five worked. However,
the other three gave the error:
"The upgrade patch cannot be installed by the Windows
Installer service because the program to be upgraded may
be missing, or the upgrade patch may update a different
version of the program. Verify that the program to be
upgraded exists on your computer and that you have the
correct upgrade patch."

These were: Access 2002 Runtime Update: KB813617,
4/30/2003; Office XP WordPerfect 5.x Converter Security
Patch: KB824938, 9/3/2003; and Access 2002 Runtime
Security Patch: KB827430, 9/3/2003.
The release patches were applied in reverse chronological
order.
I don't get it?
jt