A customer had different DNS (windows) names then VM names (the names that you see in vCenter) and wanted to change them.
Here is how you can easily do that :
Choose to migrate (storage vmotion) the server to a different datastore.
(This can be local or shared storage)
When the files are moved to the new datastore you can easily migrate them back to their original location. You will also see that the individual names are changed also.
Update : Using ESXi 5 it’s a known issue that only the directory name changes, now the files within. This will be fixed in feauture releases.