Description:
------------
This is quite interesting. Appeared after upgrading to 5.2.4 and broke my code.

It's great that objects are finally destroyed in the right order, but a whole lot of code still relies on "destroy all" or "cleanup" functions.

What struck me is that as of 5.2.4, my object in the moment of calling it's destructor, in global scope, appears as NULL.

I've also devised a simple and dirty workaround, which is found in the code below.

Thanks!

Reproduce code:
---------------
class foo {
	function __construct(){
		echo "Constructed foo\n";
	}
	
	function getDb(){
		echo "Getting DB";
	}
	
	function __destruct(){
		echo "Destructing foo\n";
		echo "Trying to destruct bar\n";
		global $bar;
		
		if(false){ // DIRTY WORKAROUND
			global $foo;
			$foo = $this;
		}
		
		$bar->__destruct();
	}
}

class bar {
	protected $destroyed = false;
	
	function __construct(){
		echo "Constructed bar\n";
	}
	
	function __destruct(){
		if(!$this->destroyed){
			echo "  Destructing bar\n";
			global $foo;
			echo "  Our global parent, foo, is of type ".gettype($foo)."\n";
			$this->destroyed = true;
		}
	}
}

$bar = new bar();
$foo = new foo();

echo "--\nScript finishes...\n";

Expected result:
----------------
Constructed bar
Constructed foo
--
Script finishes...
Destructing foo
Trying to destruct bar
  Destructing bar
  Our global parent, foo, is of type object

Actual result:
--------------
Constructed bar
Constructed foo
--
Script finishes...
Destructing foo
Trying to destruct bar
  Destructing bar
  Our global parent, foo, is of type NULL