Description:
------------
If I store an array containing references to a single value then I believe the reference set should be maintained when I fetch the value, behaving as though it had been serialized and deserialized. In the test case here only 1 member of the reference set is actually modified though the reference counts suggest that the set still exists.

Reproduce code:
---------------
<?php

$n = null;

// initialise an array with reference set
$s = 'some string';
$a[] =& $s; 
$a[] =& $s; 
$a[] =& $s; 
$s =& $n; // so the reference count is clear

debug_zval_dump($a);
var_dump(apc_store('a', $a));
$a = apc_fetch('a');

// modifiy it
$s =& $a[0];
$s = 'other string';
$s = & $n;

debug_zval_dump($a);

?>


Expected result:
----------------
array(3) refcount(2){
  [0]=>
  &string(11) "some string" refcount(3)
  [1]=>
  &string(11) "some string" refcount(3)
  [2]=>
  &string(11) "some string" refcount(3)
}
bool(true)
array(3) refcount(2){
  [0]=>
  &string(12) "other string" refcount(3)
  [1]=>
  &string(12) "other string" refcount(3)
  [2]=>
  &string(12) "other string" refcount(3)
}


Actual result:
--------------
array(3) refcount(2){
  [0]=>
  &string(11) "some string" refcount(3)
  [1]=>
  &string(11) "some string" refcount(3)
  [2]=>
  &string(11) "some string" refcount(3)
}
bool(true)
array(3) refcount(1){
  [0]=>
  &string(12) "other string" refcount(4)
  [1]=>
  &string(11) "some string" refcount(4)
  [2]=>
  &string(11) "some string" refcount(4)
}