Ilia Alshanetsky, release manager of PHP 5.1, has published the first release candidate of the upcoming 5.1.3 version of PHP. It's mainly a bug fix release, but the PCRE library was updated to version 6.6 and the CGI interface has been updated quite a bit as well. Other items improved included updates to the SPL, Reflection APU, cURL support and the GD functionality. The SimpleXML engine was also updated to allow for the use of namespaces with the addChild and addAttribute functions.

You can grab this latest release candidate from Ilia's site and you can check out the Changelog here.