ESXi should continue to operate normally despite that message being logged. It's not a PSOD, which would paint the whole screen bright pink and would completely stop ESXi from continuing.
If you are not using any unusual vmkernel configuration settings or unusual host firmware (BIOS/EFI) configuration, the message often indicates a problem with the host firmware itself. You should try to obtain a firmware update from your system board vendor. For more information, refer to the following KB article: ESX 4.0 Update 1 boot error: Can't boot system as genuine NUMA (1016141) | VMware KB
Cheers,
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Darius