There is a serious bug that causes the licenses to expire in Service Pack 2 of VMware ESX 3.5. This makes it impossible to restart any virtual server guest on the host. The workaround is to set the host date prior to 8/12/08, but if you're synching your virtual server guests with the host, this can cause serious problems with Active Directory (AD) because the time will be off. If you do change back the date on the host, make sure that all of the virtual server guests that run on ESX do not synch their time with the ESX host. This is an option in the VMware tools that run on the virtual server guest. This should be resolved by Wednesday.