Fixed inconsistency of values of used_tables_cache and
  const_item_cache for Item_func_isnull objects (bug #1990).

Fixed compiler warnings (a lot of hidden variables detected by the Forte compiler)
Added a lot of 'version_xxx' strings to 'show variables'
Prevent copying of TMP_TABLE_PARAM (This caused core dump bug on Solaris)
Fixed problem with printing sub selects to debug log

Changed ~Item_func_in() to call cleanup() (to fix memory leak)
Fixed test_multi_statements() test in client_test

New multi-key-cache handling. This was needed becasue the old one didn't work reliable with MERGE tables.
ALTER TABLE table_name ... CHARACTER SET  ... now changes all char/varchar/text columns to the given character set
(One must use ALTER TABLE ... DEFAULT CHARACTER SET ... to change the default character set)
Fixed that have_compress is detected properly (fixes problems with func_compress.test on platforms without zlib)
New syntax for CACHE INDEX ('keys' is optional if no index name is given and one mentions the key cache name only ones)
Removed compiler warnings
Added mysql_set_server_option() to allow clients like PHP to easaily set/reset the multi-statement flag.

added code covarage for functions convert(), nullif(), crc32(), is_used_lock(), char_lengtrh(), bit_xor()
added string length for more speed
made code covarage for print() method of Item
fixed printability of some items (SCRUM) (WL#1274)

code cleanup

new EXPLAIN parameter to show real query as it was interpreted
(SCRUM) (WL#1274)

(SCRUM) (WL#1274)

independent ALL/ANY subselect on top of WHERE clause (subselect without GROUP BY or aggregate functions) optimisation

(SCRUM) (WL#1086)

This allowed to reuse a lot of code. 

args[0] is used instead. This allowed to resuse a lot of code.

  ROW('a','b','c) = ROW('A' collate latin1_bin,'b','c') returns 0
When a number is compared to a string, character sets and 
collations are not aggregated. e.g. this returned error in 4.1.0:

SELECT 1=_latin2'1';
because character sets was aggregated, and 1 was considered as
a string of latin1 charset during this aggregation.

fixed dependence of items from reduced subquery
(SCRUM)

removed outer resolving flag (because of movingtransformation after fix_fields)

  Added inequality predicate to range optimization

REPLACE() now processed arguments collations according to standard

CONCAT() and other string functions. This allows to reuse a lot
if code and to simplify further development.

It's a combination of collation and its derivation (precedence order)

repeat, reverse, quote, soundex, substring
Test func_str has been extended to check them

Added initialization of all important global variables

removed "of is null" if it is possible
  (this cset should be SCRUM related, but not approved as scrum task yet)

comparison" table, "SQL Complete, Really", page 162

  use of new argument
sql_analyse.h:
  macros from mysql_priv.h. Should be deleted soon.
mysql_priv.h:
  _default_charset_info has been removed
item_cmpfunc.h:
  Use cmp_charset
hostname.cc, hash_filo.h:
  Move charset to constructor argument

into the only one sortcmp() with additional
CHARSET_INFO *cmp_charset argument.

Novell patches