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
)