Your post makes no sense, unless you meant to say 'neither' instead of 'either'
Are you using a '#! <path-to-perl>' line at the top of your script? If so, does that resolve to the same perl as those used in the latter part of your post?
If the script does not complain, does it work?
If you have any doubts, can't you just install it? Even if you don't have access to the 'standard' include areas, you can create your own, and add it to @INC inside your script...