In PHP4 versus PHP5, use simplexml, domxml or xml?

Im creating a script that pulls xml data from a central server, then stores it locally to be read. The script will resides on 100's of different servers. Some of these servers have php4, some have php5, some have domxml, some have simplexml, some have regular xml... Ive done what i needed to in domxml and in simple xml... My question is does anyone have a easy way to match the following examples...

CODE EXAMPLE 1: SERVER WITH SIMPLEXML RUNS...
  $domaininfo = simplexml_load_file($localxmlfile);

CODE EXAMPLE 2: SERVER WITH DOM XML RUNS...
  $xml = file_get_contents($localxmlfile);
  $doc = domxml_open_mem($xml); //(PHP 4 >= 4.2.0)
  $domaininfo = xmlnode2array($doc->root());

I need domaininfo to be an array containing the xml data... the xml data has children, its not just one level deep... heres an example of the data being pulled...

EXAMPLE XML:
<domaininfo>
<nid>378</nid>
<title>Best+Web</title>
<created>1212617890</created>
<changed>1212799071</changed>
<url>http://www.domain.com</url>

<flash_header>
<nid>376</nid>
<title>Digital+Media+2</title>
<created>1212617812</created>
<changed>1212787780</changed>
<movie>
/flash/flas2.swf
</movie>
<checksum>fb539422b5f4cbd1e0b1437f98859857</checksum>
<size>529991</size>
<width>780</width>
<height>300</height>
</flash_header>

<style_sheet>
<nid>370</nid>
<title>Basic</title>
<created>1212612552</created>
<changed>1212788566</changed>
<style>
some style sheet code
</style>
</style_sheet>

<pages>

<page>
<nid>379</nid>
<title>Media+Design</title>
<field_weight>2</field_weight>
<url>mediadesign.html</url>
</page>

<page>
<nid>380</nid>
<title>Design+Services</title>
<field_weight>0</field_weight>
<url>designservices.html</url>
</page>

<page>
<nid>381</nid>
<title>Design+Tools</title>
<field_weight>5</field_weight>
<url>graphic-design-tools.html</url>
</page>

</pages>

</domaininfo>


WHAT I NEED:
i need a NON domxml and NON simplexml example that will work in php4 of how to convert xml into an array... can you help point me in the right direction and/or provide an example??