Description:
------------
PHP-Version 5.5.11

http://www.php.net/manual/en/class.thread.php

class Thread should accept closures.

Test script:
---------------
<?php
   error_reporting(~0);

   class T extends Thread
   {
      private $cCallback;
      private $i;

      /**
       * @param Closure $cCallback
       * @param int $i unique Thread number
       */
      function __construct(Closure $cCallback, $i)
      {
         $this->cCallback = $cCallback;
         $this->i = $i;
         var_dump($this->cCallback);
      }

      function run()
      {
         call_user_func_array($this->cCallback, [1]);
      }
   }
   
   // Callback function:
   $cCallback = function($i) 
   { 
      echo $i." finished\n"; 
   };
   
   $oT = new T($cCallback, 1);
   $oT->start(); 
?>

Expected result:
----------------
var_dump($this->cCallback); // Closure

Actual result:
--------------
var_dump($this->cCallback); // NULL