pg_depend dependency and concurrent DDL issues in PG 8.3.x

Hi,

Am referring to the following conversation:

http://archives.postgresql.org/pgsql-bugs/2007-12/msg00190.php

To summarize, in 8.3.x due to improper locking and concurrency issues
in the DROP OBJECT codepath, for example if one tries to drop an index
while dropping the table from another session, we end up with orphaned
index objects. There are similar issues related to orphaned triggers,
"tuple concurrent update" errors etc. in that thread.

> s1=> CREATE TABLE x(i integer);
>
> s2=> BEGIN;
> s2=> CREATE UNIQUE INDEX x_pkey ON x(i);
>
> s1=> DROP TABLE x;
> (Session hangs)
>
> s2=> COMMIT

I see that all these issues have been fixed and committed by Tom via
git commitid: 281a724d on 6th June, 2008. Was wondering why this fix
is not in these supported branches like 8.3.13 for example. Kinda
confused..

Regards,
Nikhils