Can't get PostgreSQL to run in Debian Lenny

I'm trying to install PostgreSQL 8.3 on Debian Lenny (kernel 2.6.26-2-686) using the package manager:

sudo apt-get install postgresql-8.3 postgresql-client-8.3 postgresql-contrib-8.3 postgresql-common

When deploying the package postgresql-common, the following warning is displayed:

supported_versions: WARNING: Unknown Debian release: 5.0.4

I wonder if this is related to the problem I describe below.

Next I try to launch the database server but it doesn't have any effect, neither any logs are generated.

sudo /etc/init.d/postgresql-8.3 start

Does anybody have a clue of what might be going on?

UPDATE: These are the contents of sources.list:

deb http://security.debian.org/lenny/updates main contrib
deb-src http://security.debian.org/lenny/updates main contrib
deb http://volatile.debian.org/debian-volatile lenny/volatile main contrib 
deb-src http://volatile.debian.org/debian-volatile lenny/volatile main contrib
deb http://http.us.debian.org/debian stable main contrib non-free

WORKAROUND: Thanks to @lg for pointing out that this particular package is buggy. A possible workaround is to install PostgreSQL 8.4 from the Debian backports repository:

Added the following line to /etc/apt/sources.list:

deb http://www.backports.org/debian lenny-backports main contrib non-free

And executed:

apt-get install debian-backports-keyring
apt-get update
apt-get -t lenny-backports install postgresql-8.4

The server then starts up automatically.