It may be that localhost is either misconfigured, or the url is wrong. Now you'll need to do some error checking. I put a test script together to get you started. 
#!/usr/bin/perl

use strict;
use warnings;
use Net::INET6Glue;
require RPC::XML;
require RPC::XML::Client;

my $server_url = 'http://test.xmlrpc.wordtracker.com';

my $cli = RPC::XML::Client->new($server_url);
my $res = $cli->send_request( 'ping', 'guest' );
if ( ${$res} == 1 ) {
    print "Successfully pinged guest account", "\n";
    exit 0;
}
else {
    print "There were problems...\n";
    exit 0;
}

[download]
Experiment with it. If you continue to have problems, post again.

In reply to Re^3: IPv6 support for XML-RPC modules by Khen1950fx
in thread IPv6 support for XML-RPC modules by daphnaw

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.