You just need to find out which ports are available for you to listen on. Then simply setup a socket listener on one of those ports.

use strict;

use IO::Socket;

my $Socket = IO::Socket::INET->new(
                LocalPort => 8190,
                Type      => SOCK_STREAM,
                Reuse     => 1,
                Listen    => 1 );
my ($client);
while($client = $Socket->accept()){
  ##Do something with socket handle
}
[download]

This one for example, listens on 8190.

- Tom