The PHP Development Team would like to announce the immediate release of PHP 4.4.0.
This is a maintenance release that addresses a serious memory corruption problem within PHP concerning references. If references were used in a wrong way, PHP would often create memory corruptions which would not always surface or be visible. In other cases it could cause variables and objects to change type or class unexpectedly. If you encountered strange behavior like this, this release might fix it. The increased middle digit was required because the fix that corrected the problem with references changed PHP's internal API, breaking binary compatibility with the PHP 4.3.* series. This means that all binary extension modules need to be recompiled in order to work with this release.
As part of the solution for the reference bug, you are very likely to find that your own or third-party PHP scripts, considered 'clean' code under previous versions of PHP, will now throw an E_NOTICE when references are incorrectly used in the script. This is intended to alert developers to minor errors in their approach, and does not affect the script's performance in any other way.
Besides the reference problem, this release also fixes numerous other bugs, including a small security problem with our bundled shtool.
For a full list of changes in PHP 4.4.0, see the ChangeLog.