in reply to LWP::SIMPLE fails on certain URL

Is it possible that there some security system on this page that will not allow it to be retrieved?

Yes. It's also possible that the site is reponding to the User-Agent: header, though that seems unlikely since other using LWP have been able to fetch this page. You might give it a try, though.

To set User-Agent: yourself, you'll need to use LWP::UserAgent instead of LWP.