vmware-esx-4-1-uuid
the .vmx file contains at least 3 uuid's
two strings of hex numbers with a dash between
e.g. uuid.bios = "42 3e fd 15 e7 18 18 17-91 f0 68 bc 17 99 97 81"
uuid.bios (which changes depending on whether you've "moved" or "copied it") uuid.vc (which does not seem to change uuid.location (which does change depending on location of the file?)
you can modify the .vmx file (with the VM turned off) if necessary (e.g. roll back to a previous version if you accientally clicked "copied" instead of moved)...