Log Message:
Changes 8.3.6:
* Make "DISCARD ALL" release advisory locks, in addition to
  everything it already did
  This was decided to be the most appropriate behavior. This could
  affect existing applications, however.
* Fix whole-index GiST scans to work correctly
  This error could cause rows to be lost if a table is clustered on a
  GiST index.
* Fix crash of xmlconcat(NULL)
* Fix possible crash in ispell dictionary if high-bit-set characters
  are used as flags
  This is known to be done by one widely available Norwegian
  dictionary, and the same condition may exist in others.
* Fix misordering of pg_dump output for composite types
  The most likely problem was for user-defined operator classes to be
  dumped after indexes or views that needed them.
* Improve handling of URLs in headline() function
* Improve handling of overlength headlines in headline() function
* Prevent possible Assert failure or misconversion if an encoding
  conversion is created with the wrong conversion function for the
  specified pair of encodings
* Fix possible Assert failure if a statement executed in PL/pgSQL is
  rewritten into another kind of statement, for example if an
  "INSERT" is rewritten into an "UPDATE"
* Ensure that a snapshot is available to datatype input functions
* Make it safer for SPI-using functions to be used within datatype
  I/O; in particular, to be used in domain check constraints
* Avoid unnecessary locking of small tables in "VACUUM"
* Fix a problem that sometimes kept "ALTER TABLE ENABLE/DISABLE RULE"
  from being recognized by active sessions
* Fix a problem that made UPDATE RETURNING tableoid return zero
  instead of the correct OID
* Allow functions declared as taking ANYARRAY to work on the
  pg_statistic columns of that type
  This used to work, but was unintentionally broken in 8.3.
* Fix planner misestimation of selectivity when transitive equality
  is applied to an outer-join clause
  This could result in bad plans for queries like ... from a left
  join b on a.a1 = b.b1 where a.a1 = 42 ...
* Improve optimizer's handling of long IN lists
  This change avoids wasting large amounts of time on such lists when
  constraint exclusion is enabled.
* Prevent synchronous scan during GIN index build
  Because GIN is optimized for inserting tuples in increasing TID
  order, choosing to use a synchronous scan could slow the build by a
  factor of three or more.
* Ensure that the contents of a holdable cursor don't depend on the
  contents of TOAST tables
* Fix memory leak when a set-returning function is terminated without
  reading its whole result
* Fix encoding conversion problems in XML functions when the database
  encoding isn't UTF-8
* Fix "contrib/dblink"'s dblink_get_result(text,bool) function
* Fix possible garbage output from "contrib/sslinfo" functions
* Fix incorrect behavior of "contrib/tsearch2" compatibility trigger
  when it's fired more than once in a command
* Fix possible mis-signaling in autovacuum
* Support running as a service on Windows 7 beta
* Fix ecpg's handling of varchar structs
* Fix configure script to properly report failure when unable to
  obtain linkage information for PL/Perl
* Make all documentation reference pgsql-bugs and/or pgsql-hackers as
  appropriate, instead of the now-decommissioned pgsql-ports and
  pgsql-patches mailing lists
* Update time zone data files to tzdata release 2009a (for Kathmandu
  and historical DST corrections in Switzerland, Cuba)