?absolute path for "use" clause

I'm using a web presence provider that provides limited
capability for CGI programming - they provide perl4 and perl5
interpreters, but no modules/libraries (I think this is an
erroneous decision, but...), and they provide *IX shell (sh and
tcsh, I believe).  As a result of their decisions, if I want to
use any perl5 modules, I must, according to their support staff,
supply the full pathname of the module.  None of the references I
have on either perl or CGI discuss this (or at least I couldn't
find any such discussion).  Would someone please be so kind as to
enlighten me?

Please copy me by email; while I _do_ check news at least three
times per week, I have extremely strong reason to believe that my
provider's upstream provider is _not_ providing a complete feed,
irrespective of their statement to my provider (and my provider's
to me).