Description:
------------
When using foreach($arr as $index => &$item), the $item reference does not always allow a modification of the referenced element.

Reproduce code:
---------------
<?
$items = array (array (1), array (1));
foreach ($items as $index => &$one_item) {
	printf ("C1 IDENTICAL: %u\n", $items [$index] === $one_item);
	each ($items [$index]);
	printf ("C2 IDENTICAL: %u\n", $items [$index] === $one_item);
	$one_item = 678;
	printf ("C3 IDENTICAL: %u\n", $items [$index] === $one_item);
}
?>


Expected result:
----------------
C1 IDENTICAL: 1
C2 IDENTICAL: 1
C3 IDENTICAL: 1
C1 IDENTICAL: 1
C2 IDENTICAL: 1
C3 IDENTICAL: 1


Actual result:
--------------
C1 IDENTICAL: 1
C2 IDENTICAL: 1
C3 IDENTICAL: 1
C1 IDENTICAL: 1
C2 IDENTICAL: 1
C3 IDENTICAL: 0