Well that test script works for me (running as root)

#!/usr/bin/perl

use warnings;

use Nmap::Scanner;
use Data::Dumper;

my $scan = Nmap::Scanner->new();
$scan->add_target('localhost');
$scan->add_scan_port('16310-16316');
$scan->tcp_syn_scan();
my $results = $scan->scan();

print Dumper($results);
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~# ./test.pl 
$VAR1 = bless( {
                 'ALLHOSTS' => {
                                 'Nmap::Scanner::Address=HASH(0x19a186
+0)' => bless( {
                                                                      
+                'ports' => {
..snip...                                            'Nmap::Scanner::P
+ort' ),
...
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(I truncated the answer as it's rather too verbose, but rest assured it's showing the port status) This is using Nmap::Scanner 1.0

# perl -v

This is perl 5, version 12, subversion 4 (v5.12.4) built for x86_64-li
+nux-gnu-thread-multi
(with 45 registered patches, see perl -V for more detail)
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standard perl that comes with Ubuntu 11.10 (64bit)

# nmap -V

Nmap version 5.21 ( http://nmap.org )
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