This method, SplObjectStorage::getInfo() does NOT exist on PHP 5.2.13.
However, PHP 5.3.2 and above does have it. To find out yourself, use this snippet.
$> php -r "print_r(get_class_methods(new SplObjectStorage()));"
Results for PHP 5.2.13
====
Array
(
[0] => attach
[1] => detach
[2] => contains
[3] => count
[4] => rewind
[5] => valid
[6] => key
[7] => current
[8] => next
[9] => unserialize
[10] => serialize
)
Results for PHP 5.3.2
=====
Array
(
[0] => attach
[1] => detach
[2] => contains
[3] => addAll
[4] => removeAll
[5] => getInfo
[6] => setInfo
[7] => count
[8] => rewind
[9] => valid
[10] => key
[11] => current
[12] => next
[13] => unserialize
[14] => serialize
[15] => offsetExists
[16] => offsetSet
[17] => offsetUnset
[18] => offsetGet
)