I'm not a network admin, but my guess is that one or all of those machines have been compromised, possibly because of an existing software hole, and they're keeping DNS shut down until they can all be rebuilt from scratch.
Btw, I don't think that those machines are necessarily close together. The IPs are, but the IPs probably translate to dispersed locations inside the MSFT firewall. Or so I'd expect. But perhaps I expect too much.
Marco
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> Marco Anglesio | Chance favours <
> mpa at the-wire.com | the prepared mind <
> http://www.the-wire.com/~mpa | --Louis Pasteur <
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