Predefined Classes in PHP5

I am wondering about the "Predefined Classes" for PHP5. I see that this page: http://us3.php.net/manual/en/reserved.classes.php and http://devzone.zend.com/manual/view/page/reserved.classes.html and http://livedocs.phpdoc.info/index.php?l=en&q=reserved Doesn't have much on the new classes that are available with php5. That page only shows two (2) new predefined classes for PHP5 But, as you can see from the first post on that page, there seem to be much more then 2 new classes. I have done some googling for some information about all the new classes, but I can't seem to find anything about them. So, to my question. Does anybody have a place they can refer me to to find out about all the available classes in PHP5. Granted that I don't have all the various extensions loaded, so I don't have access to the various classes. I would, however, like to be able to read about them someplace. Any tips? Jim Lucas