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Other than shutting down the VM and locally copying it to the new vCenter, do we have any other method?
1) If your datastore is shared with both ESX 3.5 and ESXi 4.1 host, Shutdown the VM and remove from inventory from ESX 3.5, Add the VM on ESXi 4.1 and Upgrade VMware tools and virtual hardware and start using the VM
2) If you are running ESX 3.5 U5 you can add the host to vCenter 4.1 and them migrate the VM to ESXi 4.1 and Upgrade VMware tools and virtual hardware and start using the VM
3) Use VMware Converter to migrate the VM to ESXi 4.1