I recently encountered this very same issue, and got good advice from the brethren.

As brother Fletch suggested,
my $url  = new URI($site);
in my code instead of
my $url  = new URI::URL($site);
did the trick for me, and seemed to be the cleanest solution.
    cheers,
    Don
    striving toward Perl Adept
    (it's pronounced "why-bick")