Other changes to extensions
New Global Constants
Migrating from PHP 5.2.x to PHP 5.3.x
PHP Manual

## New Classes

The following classes were introduced in PHP 5.3.0:

Date/Time:

- DateInterval
- DatePeriod

Phar:

- Phar
- PharData
- PharException
- PharFileInfo

SPL:

- FilesystemIterator
- GlobIterator
- MultipleIterator
- RecursiveTreeIterator
- SplDoublyLinkedList
- SplFixedArray
- SplHeap
- SplMaxHeap
- SplMinHeap
- SplPriorityQueue
- SplQueue
- SplStack