Interesting but Oooops! .. I like the note at the end “Microsoft will not be providing any hotfixes, engine updates, or program fixes to automatically correct this issue.”
Source: http://blogs.technet.com/fss/archive/2008/08/28/microsoft-av-scan-engine-updating-issue.aspx
Microsoft is aware of an issue with the Microsoft AV engine not updating on some installations of Antigen and Forefront Server Security products. Not all installations of the products are experiencing this issue, however all products may be affected.
The issue arose because the aveMicrosoft.dll in one of the Microsoft AV engine updates was marked as hidden, causing all subsequent updates to fail when attempting to delete this file. When that occurs, the engine is rolled back. This means that installations experiencing this problem are running with an outdated version of the Microsoft AV engine.
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