I modified the previous script, so that it is associative. I find it more useful that way. BTW I prefer strtolower() things, but that's not mandatory at all.

<?php

$file = "data.xml";
$depth = 0;
$tree = array();
$tree['name'] = "root";
$stack[] = &$tree;

function startElement($parser, $name, $attrs) {
   global $depth;
   global $stack;
   global $tree;
  
   $element = array();
   foreach ($attrs as $key => $value) {
       $element[strtolower($key)]=$value;
   }

   end($stack);
   $stack[key($stack)][strtolower($name)] = &$element;
   $stack[strtolower($name)] = &$element;
   
   $depth++;
}

function endElement($parser, $name) {
   global $depth;
   global $stack;

   array_pop($stack);
   $depth--;
}

$xml_parser = xml_parser_create();
xml_set_element_handler($xml_parser, "startElement", "endElement");
if (!($fp = fopen($file, "r"))) {
   die("could not open XML input");
}

while ($data = fread($fp, 4096)) {
   if (!xml_parse($xml_parser, $data, feof($fp))) {
       die(sprintf("XML error: %s at line %d",
                   xml_error_string(xml_get_error_code($xml_parser)),
                   xml_get_current_line_number($xml_parser)));
   }
}
xml_parser_free($xml_parser);
$tree = end(end($stack));
echo "<pre>";
print_r($tree);
echo "</pre>";

?>