Moving VM from ESX 3.5 to ESXi 4.1

I have a situation wherein I have a VM in a vCenter 2.5.4 with ESX 3.5 hosts and I need to migrate it to vcenter 4.1 update 3 with ESXi 4.1 hosts.

Other than shutting down the VM and locally copying it to the new vCenter, do we have any other method?

Another query I have is regarding licences.  I have the above ESX 3.5 hosts with 4 CPU licence.  Is there anyway I can upgrade the licence of the ESX 3.5 hosts from 4 to 8 ?

Regards,

Sunil