Description:
------------
Recursive object reference comparisons fail in PHP4.x.

Alternative to my "exptected result" below, I would 
settle for one of a couple of things.  One would be a 
boolean comparison function that returns true if two 
references point to the same data, or another could be 
simply a boolean function that returns true if two 
objects are the same (with recursing to all the values).

I'm aware the Zend Engine 2/PHP5 identity operator works 
in the fashion I'd like now, but I'd still consider this 
a bug for Zend Engine/PHP4.

Reproduce code:
---------------
// key failing element here is B::is_ref

class A {
  var $a_ref;
  function set_ref (&$obj) {
    $this->a_ref =& $obj; } }
class B {
  var $b_ref;
  function set_ref (&$obj) {
    $this->b_ref =& $obj; }
  function is_ref (&$obj) {
    if ($obj === $this->b_ref)
      return true; } }

$a = new A; $b = new B;
$a->set_ref ($b); $b->set_ref ($a);

var_dump ($b->is_ref ($a));

Expected result:
----------------
I would expect that "if ($obj === $this->b_ref)" would 
return true if they (the two object references being 
compared) referenced the same object, and 
false if they didnt.  Please see my description, as 
well.

Actual result:
--------------
"
Fatal error: Nesting level too deep - recursive 
dependency? in /path-to/test.php on line 12
"