Merge trift2.:/MySQL/M50/push-5.0

into  trift2.:/MySQL/M51/push-5.1


mysql-test/r/derived.result:
  Auto merged
mysql-test/r/ps_2myisam.result:
  Auto merged
mysql-test/r/ps_3innodb.result:
  Auto merged
mysql-test/r/ps_4heap.result:
  Auto merged
mysql-test/r/ps_5merge.result:
  Auto merged
BitKeeper/deleted/.del-ps_6bdb.result:
  Auto merged
mysql-test/r/sp.result:
  Auto merged
mysql-test/r/type_date.result:
  Auto merged
mysql-test/r/type_datetime.result:
  Auto merged
mysql-test/suite/ndb/r/ps_7ndb.result:
  Auto merged
mysql-test/t/sp.test:
  Auto merged
mysql-test/t/type_date.test:
  Auto merged
sql/field.cc:
  Auto merged
sql/item_func.cc:
  Auto merged
sql/item_timefunc.cc:
  Auto merged
sql/sql_cache.cc:
  Null merge of a 5.0 patch, by order of the original author via IRC.