Merging 4.1 to 5.0.

BitKeeper/etc/ignore:
  auto-union
BitKeeper/etc/logging_ok:
  auto-union
client/mysqltest.c:
  Auto merged
configure.in:
  Auto merged
include/my_sys.h:
  Auto merged
include/mysql_com.h:
  Auto merged
libmysql/libmysql.c:
  Auto merged
libmysqld/Makefile.am:
  Auto merged
libmysqld/lib_sql.cc:
  Auto merged
myisam/mi_check.c:
  Auto merged
myisam/myisamchk.c:
  Auto merged
myisam/myisamdef.h:
  Auto merged
mysql-test/r/func_group.result:
  Auto merged
mysql-test/r/func_time.result:
  Auto merged
mysql-test/r/null.result:
  Auto merged
mysql-test/r/query_cache.result:
  Auto merged
mysql-test/r/rpl_server_id2.result:
  Auto merged
mysql-test/r/select.result:
  Auto merged
mysql-test/r/subselect.result:
  Auto merged
mysql-test/r/variables.result:
  Auto merged
mysql-test/t/rpl000015.test:
  Auto merged
mysql-test/t/rpl_error_ignored_table.test:
  Auto merged
mysql-test/t/rpl_log.test:
  Auto merged
mysql-test/t/rpl_log_pos.test:
  Auto merged
mysql-test/t/rpl_max_relay_size.test:
  Auto merged
mysql-test/t/rpl_relayrotate.test:
  Auto merged
mysql-test/t/rpl_rotate_logs.test:
  Auto merged
mysql-test/t/rpl_server_id2.test:
  Auto merged
mysql-test/t/subselect.test:
  Auto merged
mysql-test/t/variables.test:
  Auto merged
mysys/my_pthread.c:
  Auto merged
netware/BUILD/compile-netware-all:
  Auto merged
netware/BUILD/compile-netware-standard:
  Auto merged
netware/BUILD/mwenv:
  Auto merged
netware/Makefile.am:
  Auto merged
netware/my_manage.c:
  Auto merged
netware/my_manage.h:
  Auto merged
netware/mysql_test_run.c:
  Auto merged
scripts/mysql_install_db.sh:
  Auto merged
sql/Makefile.am:
  Auto merged
sql/ha_berkeley.cc:
  Auto merged
sql/ha_berkeley.h:
  Auto merged
sql/ha_innodb.cc:
  Auto merged
sql/ha_innodb.h:
  Auto merged
sql/ha_myisam.cc:
  Auto merged
sql/handler.cc:
  Auto merged
sql/handler.h:
  Auto merged
sql/item.cc:
  Auto merged
sql/item.h:
  Auto merged
sql/item_cmpfunc.cc:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/item_subselect.cc:
  Auto merged
sql/item_subselect.h:
  Auto merged
sql/item_sum.cc:
  Auto merged
sql/item_sum.h:
  Auto merged
sql/item_timefunc.cc:
  Auto merged
sql/lock.cc:
  Auto merged
sql/mysql_priv.h:
  Auto merged
sql/opt_range.cc:
  Auto merged
sql/protocol.cc:
  Auto merged
sql/protocol.h:
  Auto merged
sql/repl_failsafe.cc:
  Auto merged
sql/set_var.cc:
  Auto merged
sql/sql_acl.cc:
  Auto merged
sql/sql_base.cc:
  Auto merged
sql/sql_cache.cc:
  Auto merged
sql/sql_class.cc:
  Auto merged
sql/sql_class.h:
  Auto merged
sql/sql_db.cc:
  Auto merged
sql/sql_insert.cc:
  Auto merged
sql/sql_parse.cc:
  Auto merged
sql/sql_prepare.cc:
  Auto merged
sql/sql_select.h:
  Auto merged
sql/sql_show.cc:
  Auto merged
sql/sql_string.cc:
  Auto merged
sql/sql_string.h:
  Auto merged
sql/sql_table.cc:
  Auto merged
sql/sql_union.cc:
  Auto merged
sql/sql_yacc.yy:
  Auto merged
tests/client_test.c:
  Auto merged

sql/sql_cache.cc

@@ -1517,13 +1517,28 @@ ulong Query_cache::init_cache()
   VOID(hash_init(&queries, &my_charset_bin, def_query_hash_size, 0, 0,
 		 query_cache_query_get_key, 0, 0));
 #ifndef FN_NO_CASE_SENCE
+  /*
+    If lower_case_table_names!=0 then db and table names are already 
+    converted to lower case and we can use binary collation for their 
+    comparison (no matter if file system case sensitive or not).
+    If we have case-sensitive file system (like on most Unixes) and
+    lower_case_table_names == 0 then we should distinguish my_table
+    and MY_TABLE cases and so again can use binary collation.
+  */
   VOID(hash_init(&tables, &my_charset_bin, def_table_hash_size, 0, 0,
 		 query_cache_table_get_key, 0, 0));
 #else
-  // windows, OS/2 or other case insensitive file names work around
+  /*
+    On windows, OS/2, MacOS X with HFS+ or any other case insensitive 
+    file system if lower_case_table_names!=0 we have same situation as 
+    in previous case, but if lower_case_table_names==0 then we should 
+    not distinguish cases (to be compatible in behavior with underlaying 
+    file system) and so should use case insensitive collation for 
+    comparison.
+  */
   VOID(hash_init(&tables,
 		 lower_case_table_names ? &my_charset_bin :
-		 system_charset_info,
+		 files_charset_info,
 		 def_table_hash_size, 0, 0,query_cache_table_get_key, 0, 0));
 #endif