After a home page change, PHP team pushed a new release PHP 5.2.1, a major stability and security enhancement of the 5.X branch, and all users are strongly encouraged to upgrade to it as soon as possible.
The majority of the security vulnerabilities discovered and resolved can in most cases be only abused by local users and cannot be triggered remotely. However, some of the above issues can be triggered remotely in certain situations, or exploited by malicious local users on shared hosting setups utilizing PHP as an Apache module. Therefore, all users of PHP are strongly advised, regardless of the version to upgrade to 5.2.1 release as soon as possible. PHP 4.4.5 with equivalent security corrections will be available shortly.
Please check the release announcement 5.2.1 for more details and full list of changes in ChangeLog PHP 5.

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