OpsMgr 2007: SP1: Agent setup may fail when MSXML Core Services 6.0 Service Pack 2 has already been installed on WIndows Server 2003

Installation fails with this information within the event log:

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Event Type: Error
Event Source: MsiInstaller
Event Category: None
Event ID: 10005
Date:  7/3/2009
Time:  1:41:56 PM
User:
Computer: DC1
Description:
Product: System Center Operations Manager 2007 Agent -- Microsoft Core XML Services (MSXML) 6.0 is required to install this application.  Please see the release notes for more information.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: 7b 45 37 36 30 30 41 39   {E7600A9
0008: 43 2d 36 37 38 32 2d 34   C-6782-4
0010: 32 32 31 2d 39 38 34 45   221-984E
0018: 2d 41 42 38 39 43 37 38   -AB89C78
0020: 30 44 43 32 44 7d         0DC2D} 
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