The following KB has released http://support.microsoft.com/kb/941811 This has the same requirement (agent multi-homing to original release and SP1 release management groups) as I covered here http://blogs.technet.com/cliveeastwood/archive/2007/10/31/kb941557-management-servers-that-are-running-the-release-version-of-system-center-operations-manager-2007-do-not-process-the-agent-event-data-from-an-agent-of-system-center-operations-manager-2007-service-pack-1.aspx
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