include/mysqld_error.h:
  add warning
sql/field.h:
  add friend class
sql/item_sum.cc:
  add function
sql/item_sum.h:
  add class
sql/lex.h:
  add lex
sql/mysql_priv.h:
  change push_warning
sql/mysqld.cc:
  add new option
sql/set_var.cc:
  add new system variable
sql/share/english/errmsg.txt:
  add new message text
sql/sql_class.h:
  change MY_ERROR class
sql/sql_error.cc:
  change push_warning
sql/sql_lex.h:
  add qorder_list for function
sql/sql_yacc.yy:
  add structure of group_concat
BitKeeper/etc/logging_ok:
  Logging to logging@openlogging.org accepted