Ilia Alshanetsky has posted the announcement that the latest release candidate in the PHP 5.2.x series - PHP 5.2.1 RC1 - is now available for download and testing.
This release is primarily aimed at improving the stability of the language and finalization of features introduced in 5.2.0. There are over 70 different bug fixes, a great deal of performance improvements for Windows users, corrections to the memory manager and the improvement in the filter functionality.
You can grab the source from these locations: