Description:
------------
I've made a block plugin for smarty templates library, it's working fine on PHP 5.1.1 and earlier, but not on 5.1.2. The reproduce code is just minimized to show how it works and how should it work.

Reproduce code:
---------------
$a = true;
while($a){
     fun1($a = false);
}

// ---------------------
$iterator = 0;
function fun1(&$repeat){
     global $iterator;
     if ($iterator > 10)
          $repeat = true;
     iterator++;
}

changing code of while to making it work as expected:
$a = true;
while($a){
     $a = false
     fun1($a);
}

Expected result:
----------------
more than 1 iteration should be executed, 

Actual result:
--------------
while executed once.