Špatné kódování

$request = xmlrpc_encode_request($method, $params, array('encoding' => "UTF-8"));
$options = array(
'http' => array(
'method' => "POST",
'header' => "Content-Type: text/xml",
'content' => $request
)
);
$context = stream_context_create($options);
$file = file_get_contents($this->url, false, $context);
$response = xmlrpc_decode($file, "UTF-8");

$request = xmlrpc_encode_request($method, $params, array('encoding' => "UTF-8"));

$request = xmlrpc_encode_request($method, $params, array('escaping' => 'markup', 'encoding' => "UTF-8"));

<member>
<name>clickthruUrl</name>
<value><string>http://www.example.cz?param=x&param2=xy</string></value>
</member>