"Though there are no major changes to functions and
methods in PHP V5.3, there are a few enhancements to help with
outstanding issues in PHP and to improve performance. This section
discusses a few of the more notable changes.
"In previous versions of PHP, the array functions atsort,
natcasesort, usort, uasort, uksort, array_flip, and array_unique
let you pass objects instead of arrays as parameters. The functions
then treat the properties of the objects as the array keys and
values. This is no longer available in PHP V5.3, so you need to
cast the objects to arrays first. Listing 3 shows how to change
your code."