Installing esxi 5.1 on a virtual machine on esxi 5.1, getting "VMWare requires the Execute Disable/No Execute CPU feature to be enabled"

Hi,

I am trying to install a ESXi server on a virtual machine in a vSphere 5.1 environment, but keep getting the purple screen with "VMWare requires the Execute Disable/No Execute CPU feature to be enabled" notification.

I have set guest OS to ESXi 5.x and CPU/MMU virtualization to Intel VT-x/AMD-v (tried both for MMU and EPT/RVI options).

Any ideas would be greatly appreciated.

Thanks!

Eli