How to emulate __destruct() in a static class?

I've coded a simple configuration class for my own framework.

There are simple functions like get(), set() or loadFile(). But all functions and variables are static.

And now I want to implement an autosave mechanism. I had the idea to create an instance (in my init() function) whose __destruct() will call the static destruct() function:

<?php

class Config
{
  static private $autoSave;
  static public function get() {} /* set(), save(), load(), etc. */

  static public function init($autoSave)
  {
    self::$autoSave = $autoSave;
    new Config();
  }
  static public function destruct()
  {
    if (self::$autoSave)
      self::save();
  }

  public function __destruct()
  {
    Config::destruct();
  }
}

?>

Are there any better solutions or is my design pattern completely wrong in this case?