InnoDB: Made LOCK TABLES behave by default like it did before MySQL 4.0.20 or 4.1.2: no InnoDB lock will be taken. Added a startup option and settable system variable innodb_table_locks for making LOCK TABLE acquire also InnoDB locks. See Section 15.17, « Restrictions sur les tables InnoDB ». (Bug#3299, Bug#5998)

The --with-openssl option for configure now accepts a path prefix as an argument. --with-openssl-includes and --with-openssl-libs still are supported, but are needed only to override the default values. (Bug#5494)

Added new --without-man option to configure to suppress building/installing the manual pages. (Bug#5379)

Fixed bug in server which caused connection stall when one of deprecated libmysqlclient functions mysql_create_db(), mysql_rm_db() were called and were going to return error. (Bug#6081)

Fixed returning wrong query result from query cache if temporary table haded real tables after putting results to query cache. (Bug#6084)

Fixed ENABLE KEYS, which failed if tmpdir ran out of space. Now, a full repair is done in this case. (Bug#5625)

Fixed an improper error message when trying to drop a table which is referenced by a FOREIGN KEY constraint. (Bug#5784)

Fixed a bug that allowed FLUSH TABLE(S) to close HANDLER tables. HANDLER tables now are re-opened after a FLUSH TABLE(S) when they are next used. However, they lose their file position if this happens. (Bug#4286)

Fixed a bug that allowed HANDLER tables with the same alias to be multiple opened. HANDLER aliases must now be unique, even though it is syntactically correct in versions below 4.1, to qualify them with their base table's database name (e.g. test_db.handler_tbl, but this will now conflict with e.g. another_db.handler_tbl). (Bug#4335)

Fixed crash when using MySQL 4.0 with privilege tables from MySQL 5.0.

InnoDB: Make the check for excessive semaphore waits tolerate glitches in the system clock (do not crash the server if the system time is adjusted while InnoDB is under load.). (Bug#5898)

mysqlimport now reads input files locally from the client host only if the --local option is given. Previously, it assumed incorrectly in some cases that files were local even without --local. (Bug#5829)

InnoDB: Fixed a bug in the InnoDB FOREIGN KEY parser that prevented ALTER TABLE of tables containing ‘#’ in their names. (Bug#5856)

Fixed a bug which resulted in erronously calculated number of examined rows in UNION's. This value is printed in the slow query log. (Bug#5879)

Fixed bug with crash of server on some values of read_rnd_buffer_size (Bug#5492)

Fixed bug which caused truncation of values read from or into TIMESTAMP fields if --new mode was enabled. (Bug#4131)

mysqladmin now returns a status of 0 even when the server denies access; such an error means theserver is running. (Bug#3120)

InnoDB: Fixed a bug introduced in 4.0.21. An assertion failed if one used mysqldump with the option -l or --opt, or if one used LOCK TABLES ... LOCAL. (Workaround in 4.0.21: use --quick and --single-transaction. (Bug#5538)

Fixed that if the slave SQL thread found a syntax error in a query (which should be rare, as the master parsed it successfully), it stops. (Bug#5711)

Fixed that if a write to a MyISAM table fails because of a full disk or an exceeded disk quota, it prints a message to the error log every 10 minutes, and waits until disk becomes free. (Bug#3248)

Fixed problem with symlinked databases on Windows being shown with SHOW DATABASES even if the database name doesn't match the given wildcard (Bug#5539)

Fixed problem introduced in 4.0.21 where a connection starting a transaction, doing updates, then FLUSH TABLES WITH READ LOCK, then COMMIT, would cause replication slaves to stop complaing about error 1223. Bug surfaced when using the InnoDB innobackup script. (Bug#5949)