Description:
------------
I've created a user-defined list type - a bit like the ubiquitous ArrayList - and wrapped it in another class, which exposes part of the internal list's interface... OK, so nothing radical so far.

My problem is that when I make use of the list's exposed interface in the wrapper class, it becomes a reference type for no apparent reason.

Another consequence, due to a previous bug (http://bugs.php.net/bug.php?id=20993), is that if I pass the wrapper object to a function that modifies the internal list, the original object gets modified too, as though I'd passed it by reference!


Reproduce code:
---------------
<pre>
<?
	//define a user type, similar to an ArrayList
	Class MyList
	{
		var $internalArray = array();

		function Add($obj)
		{
			array_push($this -> internalArray, $obj);
		}

		function Remove($index)
		{
			unset($this -> internalArray[$index]);
		}
	}

	//create a wrapper for the above list
	Class MyListWrapper
	{ 
		var $myList;

		function MyListWrapper()
		{
			$this -> myList = new MyList();
		}

		function AddItem($item)
		{
			$this -> myList -> Add($item);
		}

		function RemoveItem($index)
		{
			$this -> myList -> Remove($index);
		}
	}

	//function that modifies the wrapper's internal list
	function UpdateListWrapper($listWrapper)
	{
		$listWrapper -> RemoveItem(0);
	}

	//1. create a new wrapper object and dump
	$listWrapper = new MyListWrapper();
	var_dump($listWrapper);

	//2. now add item to wrapper object and dump
	$listWrapper -> AddItem("id");
	var_dump($listWrapper); //notice the list is now a reference type

	//3. now pass to modification function
	UpdateListWrapper($listWrapper);

	//4. see the original has been modified, as if 
	//   call-by-reference had been used
	var_dump($listWrapper);
?>
</pre>

Expected result:
----------------
object(mylistwrapper)(1) {
  ["myList"]=>
  object(mylist)(1) {
    ["internalArray"]=>
    array(0) {
    }
  }
}
object(mylistwrapper)(1) {
  ["myList"]=>
  object(mylist)(1) {
    ["internalArray"]=>
    array(1) {
      [0]=>
      string(2) "id"
    }
  }
}
object(mylistwrapper)(1) {
  ["myList"]=>
  object(mylist)(1) {
    ["internalArray"]=>
    array(1) {
      [0]=>
      string(2) "id"
    }
  }
}


Actual result:
--------------
object(mylistwrapper)(1) {
  ["myList"]=>
  object(mylist)(1) {
    ["internalArray"]=>
    array(0) {
    }
  }
}
object(mylistwrapper)(1) {
  ["myList"]=>
  &object(mylist)(1) {
    ["internalArray"]=>
    array(1) {
      [0]=>
      string(2) "id"
    }
  }
}
object(mylistwrapper)(1) {
  ["myList"]=>
  &object(mylist)(1) {
    ["internalArray"]=>
    array(0) {
    }
  }
}