Description:
------------
When looking for list of values of a certain attribute in xml via xpath() method, the returned SimpleXMLElement object's attributes() method does not properly return array of attributes.

Reproduce code:
---------------
test.xml:

<?xml version="1.0"?>
<test>
	<sth attr="1" />
	<sth attr="2" />
	<sth attr="3" />
</test>


index.php:

<pre>
<?php

$xml = simplexml_load_file('./test.xml');
$result = $xml->xpath('//@attr');
foreach($result as $node)
{
	var_dump($node);
	foreach($node->attributes() as $attribute => $value)
		echo $atribute . " = " . (string)$value . "\n";
	echo "---\n";
}
?>
</pre>

Expected result:
----------------
object(SimpleXMLElement)#2 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "1"
  }
}
attr = 1
---
object(SimpleXMLElement)#3 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "2"
  }
}
attr = 2
---
object(SimpleXMLElement)#4 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "3"
  }
}
attr = 3
---


Actual result:
--------------
object(SimpleXMLElement)#2 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "1"
  }
}
---
object(SimpleXMLElement)#3 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "2"
  }
}
---
object(SimpleXMLElement)#4 (1) {
  ["@attributes"]=>
  array(1) {
    ["attr"]=>
    string(1) "3"
  }
}
---