mysql_server_init() now returns error code if something went wrong (Bug #2062)
Don't use my_fopen() when reading symlink information as this may cause problems when a lot of files are opened.
Free thread keys with pthread_key_delete() instead of relying on automatic free. (Bug #2062)
Fixed bug in UNION statement with alias '*'. (Bug #1249)
Fixed a bug in DELETE ... ORDER BY ... LIMIT where the rows where not deleted in the proper order. (Bug #1024).
FOUND_ROWS() could return incorrect number of rows after a query with an impossible WHERE condition.
HOW DATABASES doesn't anymore show .sym files (on windows) that doesn't point to a valid directory. (Bug #1385)