generated php code, what are the values of the constructor param?

[Simon Chu]

class SimonSaysClient implements SimonSaysIf {
  protected $input_ = null;
  protected $output_ = null;

  protected $seqid_ = 0;

  public function __construct($input, $output=null) {
    $this->input_ = $input;
    $this->output_ = $output ? $output : $input;
  }


The above code was generated, what are the expected values of $input and
$output?  I put in the facebook thrift server name (with or without the
port) as $input got this error:

PHP Fatal error:  Call to a member function writeMessageBegin() on a
non-object in
/home/simon/PROG/PHP/UTILITY/trunk/facebook/simonsays/SimonSays.php on line
47