I need to ask you one more question.
I have installed OI 151a7 with defaults and vmware-tools with default options on my latest 5.0 updated (VMkernel esxi 5.0.0 #1 SMP Release build-914586 Nov 18 2012 11:14:47 x86_64 unknown) ESXi host.
And it is the same wrong - it does crash on vmware-tools issued reboot or shutdown.
Please note it seems to be working OK, as vmware-tools install correctly, vmware-tools work and you can see tools installed from vSphere Client. When you use GUI, you will not see any difference on reboot wheter OI has shutdown correctly or it has crashed and has been reset. After reboot, it is hardly visible on the text console (before X starts) that it claims sth about coredump crash file etc.
So: Are you sure it works properly? Are you able to shutdown the machine? Could you please test it observing console of the OI machine from vSphere Client?
Thanks in advance.
Piotr