use CGI '-oldstyle_urls';

my $cgi1 = CGI->new;

{
    local $ENV{'SCRIPT_NAME'} = '/graph';

    my $cgi2 = CGI->new({
                 'channel' =>   1,
                 'size'    => 400,
                 'ysize'   => 300,
               });
    print $cgi2->url( -query_string => 1 ), "\n";

}
print $cgi1->url( -query_string => 1 ), "\n";