Object aggregation/composition - Experimental..?

Hi! I'm sifting through the possibilities with PHP and naturally one of the first things I searched for was the possibility for OO development. Now, I found chapter LXXII in the PHP manual (file generated Sun Oct 05 02:13:52 2003), but it has quite an ugly warning clause in the top: "Warning This extension is experimental [...] may change without notice in a future release of PHP. Use this extension at your own risk." In the chapter "Classes and Objects" (under "Language Reference") I found no such warning however. Now, OO dev. is what I really want in order to make any good use of PHP in the future, so this made me a bit confused. Does anyone know whether this extension is/will be a part of the core language? Thanks for any input, and bare me with me as I'm pretty new (but learning fast ;-) ) in the PHP community... All the best, VPeO