I have a couple test systems at different clients that we have tested the
Infrastructure Update on them and when it went to upgrade the SSP databases, we
have gotten the following error in the upgrade log. This makes the SSP Admin
site unavailable. Has anybody run into this issue or has a suggestion?

[SPWebTemplateSequence] [ERROR] [8/7/2008 10:07:57 PM]: Template OSRV#0:
Exception thrown in activating SPSite scoped features for SPSite with URL
"http://site.customer.com/ssp/admin" (Id=e8febd77-cb9b-49f2-b900-2054e235d7c1).
Skipping this SPSite for template upgrade. Exception:
System.InvalidOperationException: Feature '2b1e4cbf-b5ba-48a4-926a-37100ad77dee'
is not installed in this farm, and can not be added to this scope.
at Microsoft.SharePoint.SPFeatureCollection.AddInternal(Guid featureId,
SPFeaturePropertyCollection properties, Boolean force, Boolean fMarkOnly)
at Microsoft.SharePoint.SPFeatureCollection.Add(Guid featureId, Boolean
force)
at
Microsoft.SharePoint.Upgrade.SPWebTemplateSequence.ActivateSiteFeatures(List`1
lstsiteidToUpgrade, List`1& lstsiteidExceptions, List`1& lstwebinfoExceptions)