BUG #5603: pg_tblspc and pg_twoface directories get deleted when starting up service

The following bug has been logged online:

Bug reference:      5603
Logged by:          Nacho Mezzadra
Email address:      nachomezzadra@gmail.com
PostgreSQL version: 8.3.11
Operating system:   Red Hat Enterprise 5.3
Description:        pg_tblspc and pg_twoface directories get deleted when
starting up service
Details:

This issue happened not very frequently, but it happened to me 3 times, in 3
different Red Hat servers.
The thing is that when stopping the Postgresql service with the
"/sbin/service postgresql-8.3 stop" command, and after that starting it with
the "/sbin/service postgresql-8.3 start" command (haven't tried with the
restart one though), a few times both pg_tblspc and pg_twoface  directories
(inside data directory) get somehow deleted and hence the start service
command fails.  Looking in the log files I find the following error:

2010-07-19 16:54:55 ISTFATAL:  could not open directory "pg_tblspc": No such
file or directory

So I manually create the "pg_tblspc" directory, and then try to start again
the service unsuccessfully, getting this time a similar error, but saying
that pg_twoface directory doesn't exist.

After creating the pg_twoface directory, service can be successfully
started.

Please note that all these always happened running the service command as
root.
All 3 linux boxes are running over a VMWare host.