You should change to using check_vmware instead of check_esx -- the VMWare API has changes and check_esx has been replaced by check_vmware which uses the official API.
I am having the same problem as the OP. But I am not sure how to use the solution that you suggested. what do you mean by VMWare API? Where do I obtain that? sorry my english is not that good. I know there are some companies that do translation services
, perhaps I could pay one to translate it to my native language.