Postgresql 9.1 on Debian 6.0
Please keep in mind that this post was written more than 2 years ago and might be outdated.
http://serverfault.com/questions/413211/cannot-install-postgres-9-1-on-a-fresh-debian-6-0
http://serverfault.com/questions/413211/cannot-install-postgres-9-1-on-a-fresh-debian-6-0