Description:
------------
When I use preg_replace() with e modifier along with str_replace in the replace string, it doesn't work well.

Reproduce code:
---------------
HTML code ($s):

<ul style="list-style-type: square;">
<li>Megadeth -- Back to the Start, Peace Sells, Rust In Peace, Countdown to Extinction
</li><li>Ramones -- Anthology, Ramonesmania, Rocket to Russia, Too Tough To Die, Adios Amigos
</li>
</ul>

$de = array('<li>', '</li>');

$s = preg_replace("#\<ul style\="list-style-type\: square;"\>(.+?)\</ul\>#sie", "'<ul style="list-style-type: square;">'.str_replace(\"$de\", '', '$1').'</ul>'", $s);



Expected result:
----------------
I expect that all <li> and </li> get removed in the HTML part ($s).

HOWEVER, when I turn $de to a string, so it contains <li> *or* </li>, then it works.

Actual result:
--------------
<li> and </li> tags don't get removed.

This is also explained here (if it helps):

http://forum-grounds.com/viewtopic.php?p=756