This bug report was two problems:
1) LAST_INSERT_ID() returns a value which does not exist in the table
2) the reporter would want it to return the autoinc id of the updated
row.
1) is a real bug, 2) is a feature request.
In July I implemented 2) in 5.1 (which automatically fixes 1).
This has not yet been documented or released, so is changeable.
Precisely, recently Paul and a user found an easy workaround to give
2), which works in 4.1-5.0-5.1. So I can revert my code for 2),
because it's not needed, that's what I do here;
we forget about 2) (we will document the workaround).
But when I revert my code for 2), 1) comes back. We solve 1) by saying
that if INSERT ON DUPLICATE KEY UPDATE updates a row, it's like a
regular UPDATE: LAST_INSERT_ID() should not be affected (instead of
returning a non-existent value).
So note: no behaviour change compared to the last released 5.1; just
a bugfix for 1).

Bugs fixed:
- Bug #20791    valgrind errors in InnoDB
  Remove Valgrind warning of Bug #20791 : in new database
  creation, we read the doublewrite buffer magic number from
  uninitialized memory; the code worked because it was extremely
  unlikely that the memory would contain the magic number
- Bug #21784    DROP TABLE crashes 5.1.12-pre if concurrent
  queries on the table
  remove update_thd() in ::store_lock()


Also includes numerous coding style fixes, etc.  See file-level
comments for details.

into  maint2.mysql.com:/data/localhome/tsmith/bk/51

  'reorder' default off until test cases fixed.

into  maint1.mysql.com:/data/localhome/cmiller/mysql-5.1-maint

into  maint1.mysql.com:/data/localhome/cmiller/mtr_reorder/my51-mtr_reorder

  Provide a more extensible, easier-to-change way of reordering
  test cases.

into  alik.:/mnt/raid/alik/MySQL/devel/5.1-rt-merged

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1-new-maint

into  moonbone.local:/work/tmp_merge-5.1-mysql

into  shellback.(none):/home/msvensson/mysql/mysql-5.1-new-maint

into  shellback.(none):/home/msvensson/mysql/mtr/my51-mtr

into  shellback.(none):/home/msvensson/mysql/mtr/my50-mtr

Decreases test time when running a selected number of tests

into  rama.(none):/home/jimw/my/mysql-5.1-clean

mysqldump.result is wrong, will need to be cleaned up.

so that 4.1 and 5.0 tests are all in the right place and no tests are duplicated.

into  dator5.(none):/home/pappa/push_clone

into  dator5.(none):/home/pappa/push_clone

Gives slightly faster startup

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.1-maint

into  zippy.cornsilk.net:/home/cmiller/work/mysql/mysql-5.1-maint

Fixes bad merge.

into  zippy.cornsilk.net:/home/cmiller/work/mysql/no-strange-literals/my51-no-strange-literals

into  zippy.cornsilk.net:/home/cmiller/work/mysql/no-strange-literals/my50-no-strange-literals

single file is a bad practice.  

The problem was in dummy grep on AIX and HPUX.

The fix is to use more portable patterns.

The patch is only for test suite
(i.e. does not touch server codebase).

into  bk-internal.mysql.com:/data0/bk/mysql-5.1-kt

into  perch.ndb.mysql.com:/home/jonas/src/mysql-5.1

into  dator5.(none):/home/pappa/push_clone

into  dator5.(none):/home/pappa/push_clone

fixed error message

into  bodhi.local:/opt/local/work/mysql-5.1-runtime-merge