If you have a storage array that supports Hardware acceleration vaai plugins are loaded automatically. In your setup you don't need to do anything. All vaai offload command are supported and they will work.
Iyou can find the plugins loaded by using commands here
Though this is for 5.1 if it does not work let me know.
Read more information about VAAI in http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1021976
Thanks
Arvind