Try some test cases with this... I ran it on my Ultra 10 and got some interesting results. I tried pinging localhost, the assigned IP of my box, and a physically adjacent machine on a different subnet...

#!/usr/local/bin/perl -w

use Net::Ping;
use Data::Dumper;

for(@ARGV)
{
  $p = Net::Ping->new();

  $return = $p->ping($_);
  $p->close();

  print $_ . "\n";
  print Data::Dumper->Dump([$return], [qw(*$_)]);
}
[download]

--isotope
http://www.skylab.org/~isotope/