This is a bugfix release for the current production release family. It replaces MySQL 5.0.51b.

Functionality added or changed:

* Security Enhancement: To enable stricter control over the location from which user-defined functions can be loaded, the plugin_dir system variable has been backported from MySQL 5.1. If the value is non-empty, user-defined function object files can be loaded only from the directory named by this variable. If the value is empty, the behavior that is used before 5.0.67 applies: The UDF object files must be located in a directory that is searched by your system's dynamic linker. (Bug#37428)
* Important Change: Incompatible Change: The FEDERATED storage engine is now disabled by default in the .cnf files shipped with MySQL distributions (my-huge.cnf, my-medium.cnf, and so forth). This affects server behavior only if you install one of these files. (Bug#37069)
* Cluster API: Important Change: Because NDB_LE_MemoryUsage.page_size_kb shows memory page sizes in bytes rather than kilobytes, it has been renamed to page_size_bytes. The name page_size_kb is now deprecated and thus subject to removal in a future release, although it currently remains supported for reasons of backward compatibility. See The Ndb_logevent_type Type, for more information about NDB_LE_MemoryUsage. (Bug#30271)
* Important Change: Some changes were made to CHECK TABLE ... FOR UPGRADE and REPAIR TABLE with respect to detection and handling of tables with incompatible .frm files (files created with a different version of the MySQL server). These changes also affect mysqlcheck because that program uses CHECK TABLE and REPAIR table, and thus also mysql_upgrade because that program invokes mysqlcheck.
o If your table was created by a different version of the MySQL server than the one you are currently running, CHECK TABLE ... FOR UPGRADE indicates that the table has an .frm file with an incompatible version. In this case, the result set returned by CHECK TABLE contains a line with a Msg_type value of error and a Msg_text value of Table upgrade required. Please do "REPAIR TABLE `tbl_name`" to fix it!
o REPAIR TABLE without USE_FRM upgrades the .frm file to the current version.
o If you use REPAIR TABLE ...USE_FRM and your table was created by a different version of the MySQL server than the one you are currently running, REPAIR TABLE will not attempt to repair the table. In this case, the result set returned by REPAIR TABLE contains a line with a Msg_type value of error and a Msg_text value of Failed repairing incompatible .FRM file.

Previously, use of REPAIR TABLE ...USE_FRM with a table created by a different version of the MySQL server risked the loss of all rows in the table.