I know from the presentations, customer meetings and emails I get, many of you are running NT4 server as a guest under Virtual Server 2005. While NT4 itself as a guest is supported, remember that this doesn't increase the supportability of the NT4 OS itself.
However, here's a useful tip if you find that NT4 doesn't power off automatically if you instigate the shutdown through Virtual Server (it should work OK if you use the start/shutdown command). You need to enable the NT APM/Legacy support. Note that this was a deliberate step by the development team for Virtual Server to ensure that undo disks were flushed correctly. I don't have the exact specifics of the problem, but this is planned behaviour.
To resolve, you will need the hal.dll.softex.dll that's provided, but not installed, from SP4. Note you officially need SP6A anyway to run NT under Virtual Server so that shouldn't be a problem. Run through the following steps: