PHP 5.2.5

Complete Source Code
PHP 5.2.5 (tar.bz2) [7,591Kb] - 08 November 2007md5: 1fe14ca892460b09f06729941a1bb605
PHP 5.2.5 (tar.gz) [9,739Kb] - 08 November 2007md5: 61a0e1661b70760acc77bc4841900b7a
Windows Binaries
PHP 5.2.5 zip package [9,713Kb] - 08 November 2007md5: a1e31c0d872ab030a2256b1cd6d3b7d1
PHP 5.2.5 installer [19,803Kb] - 15 November 2007md5: f9396b654721d9a18c95ea6412c3d54e
Note: Updated due to problems with the original installer for this release.
PECL 5.2.5 Win32 binaries [2,879Kb] - 08 November 2007md5: a3553b61c9332d08a5044cf9bf89f2df
PHP 5.2.5 Non-thread-safe Win32 binaries [9,619Kb] - 08 November 2007md5: 41ef1582f43cfdb6e546a626b9ef93d6
PECL 5.2.5 Non-thread-safe Win32 binaries [4,114Kb] - 08 November 2007md5: 6e5ac694907b4aae080b2c9b6e83748a
Note: (Most of these PECL extension files come standard with the PHP 4 Windows binaries, but have since been moved into this separate PECL download. Files such as php_pdf.dll, php_ssh2.dll, etc.)
We have a PHP 5 / Zend Engine 2 page explaining the language level changes introduced in PHP 5. The PHP 5 ChangeLog details all the other changes