public function multicall_error($err)
{
$str = is_string($err) ? $this->xmlrpcstr["multicall_{$err}"] : $err->faultString();
$code = is_string($err) ? $this->xmlrpcerr["multicall_{$err}"] : $err->faultCode();
$struct['faultCode'] = new XML_RPC_Values($code, 'int');
$struct['faultString'] = new XML_RPC_Values($str, 'string');
return new XML_RPC_Values($struct, 'struct');
}