Download php xmlrpc:
http://phpxmlrpc.sourceforge.net/

Online document:
http://phpxmlrpc.sourceforge.net/doc-1.1/

Server:

<?php
require('phpxmlrpc/xmlrpc.inc');
require('phpxmlrpc/xmlrpcs.inc');

function foo () {
    global $xmlrpcerruser, $xmlrpcI4, $xmlrpcInt, $xmlrpcBoolean, $xmlrpcDouble, $xmlrpcString, $xmlrpcDateTime, $xmlrpcBase64, $xmlrpcArray, $xmlrpcStruct, $xmlrpcValue;
    $struct = new xmlrpcval(
        array(
            'code'    => new xmlrpcval('200', 'int'),
            'msg'    => new xmlrpcval('ok', 'string'),
        ), $xmlrpcStruct);

    return new xmlrpcresp($struct);
}

$methodCalls = array(
    "examples.foo" => array(
                "function" => "foo",
                'signature' => array(array($xmlrpcStruct))
            )
);

$xmlrpcServer = new xmlrpc_server($methodCalls, false);

$xmlrpcServer->functions_parameters_type = 'phpvals';
// define UTF-8 as the internal encoding for the XML-RPC server
$xmlrpcServer->xml_header('UTF-8');
$xmlrpc_internalencoding = 'UTF-8';
// debug level
$xmlrpcServer->setDebug(0);
// start the service
$xmlrpcServer->service();


Client:

<?php
require('phpxmlrpc/xmlrpc.inc');

$client=new xmlrpc_client('/server.php', 'xmlrpc.sample.com', 80);
//$client->setDebug(1);
$message = new xmlrpcmsg('examples.foo');

$xmlrpcdoc = $client->send($message);

if($xmlrpcdoc->faultcode()==0) {
    $response=$xmlrpcdoc->value();
    $output = var_export($response->scalarval(), true);

    print '<pre>';
    echo $output;
    print '</pre>';
} else {
     print 'Error: '.$xmlrpcdoc->faultcode().', '.$xmlrpcdoc->faultstring().'<br>';
}