This is of course a matter of legal interpretation of the terms and conditions and I am not and don't claim to be a lawyer (even though I do have some experience in legalese matters), but if you have the right to install your own programs into YOUR environment, I fail to see any reason why you would not have the right to also install your own modules in that same environment of yours, whether your own modules have been created by you or come from the CPAN (or any other source).

So long as you don't pollute the environment that they make available to every user, there should not be any problem in my view.

What is unclear in "No, you cannot add additional Perl Modules to the server"?

Written in this way it even stops you from adding your own modules.

A good case can be made that this is indeed part of the contractual agreement that allows you on their server. I agree that it is a strange rule, but "pacta sunt servanda" and not even a court can set a clear contractual clause that does not need any construction and does not break any laws, aside.

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics