src/Devedge/XmlRpc/Server/XmlRpcBuilder.php
public static function createFault($code, $message)
    {
        $response = new \SimpleXMLElement("<methodResponse></methodResponse>");
        $struct = $response->addChild("fault")->addChild("value")->addChild("struct");

        $member = $struct->addChild("member");
        $member->addChild("name", "faultCode");
        $member->addChild("value")->addChild("int", $code);

        $member = $struct->addChild("member");
        $member->addChild("name", "faultString");
        $member->addChild("value", $message);

        return $response->asXML();
    }
public static function createFault($code, $message)
    {
        $response = new \SimpleXMLElement("<methodResponse></methodResponse>");
        $struct = $response->addChild("fault")->addChild("value")->addChild("struct");

        $member = $struct->addChild("member");
        $member->addChild("name", "faultCode");
        $member->addChild("value")->addChild("int", $code);

        $member = $struct->addChild("member");
        $member->addChild("name", "faultString");
        $member->addChild("value", $message);

        return $response->asXML();
    }
creates a xml-rpc fault

@param int $code
@param string $message
@return string