Description:
------------
When upgrading to 4.3.2 this started to happen:

whenever I use

$string = preg_replace("/\[$pattern\]/",$replacement,$string)

and the $pattern is empty or does not exist, but the replacement is an array, my string is made empty.


'. /configure' '--prefix= /usr /local' '--with-apxs= /usr /local /apache-1.3.27 /bin /apxs' '--with-config-file-path= /etc' '--with-mysql= /usr' '--with-ldap' '--enable-sysvshm=yes' '--enable-sysvsem=yes' '--with-gd= /usr' '--with-gettext' '--with-xml' '--with-imap' '--enable-sockets' '--enable-ftp' '--with-regex=system' '--enable-track-vars=yes' '--enable-force-cgi-redirect=yes' '--enable-memory-limit=yes' '--enable-debug=no'

Register Globals is "on"

Reproduce code:
---------------
  $data = array(
    "field1" => "somevalue",
    "field2" => array("hmm","whassup"),
  );

  $html = '<b>[field1]</b>
  ,<h1>[field3]</h1>';

  while (list($field,$fielddata) = each ($data)) {
    $html = preg_replace("/\[$field\]/",$fielddata,$html);
  }
  print $html;
# will print nothing. however if you comment out the line "field2" etc above, it will print something


Expected result:
----------------
output should be :
<b>somevalue</b>
, <h1>[field3]</h1>

Actual result:
--------------
no output, the string $html is empty