Description:
------------
It seems there is some problem in DOMAttr (and possibly other DOM classes) implementation... DOMAttr completely ignores $value in custom class, setting it to private and using magic methods also does not work as expected

<?php

class Custom_DOMAttr extends DOMAttr {
  public $value = 'my_value';
}

$attr = new Custom_DOMAttr("name");

$attr->value = "other_value";

var_dump($attr); // object(Custom_DOMAttr)#1 (1) { ["value"]=> string(8) "my_value" }
var_dump($attr->value); // string(11) "other_value"

?>

Test script:
---------------
<?php

class Custom_DOMAttr extends DOMAttr {
  public $value = 'my_value';
}

$attr = new Custom_DOMAttr("name");

$attr->value = "other_value";

var_dump($attr);
var_dump($attr->value);

?>

Expected result:
----------------
object(Custom_DOMAttr)#1 (1) {
  ["value"]=>
  string(8) "my_value"
}
string(11) "my_value"


Actual result:
--------------
object(Custom_DOMAttr)#1 (1) {
  ["value"]=>
  string(8) "my_value"
}
string(11) "other_value"