Due to a virtualization restriction with the 32-bit VT it’s not possible to start a VM in a virtualized ESX 3.5 environment. There are a lot of people searching for the right ESX 3.5 tweak but after numerous attempts I’m beginning to doubt if it’s possible at all. The answer to this question will eventually depend on a patch from VMware that addresses the implementation of the Intel Vanderpool Technology and it’s VMX mode the right way. When you want to know more about Vanderpool and VM’s running on it, this document is very interesting.