Comment 2 for bug 383944

I spend several hours trying to fix this.

The problem is related to postgresql and how the the deb package manager of postgresql has changed the default authentification.

Simply open pg_hba.conf, for me located in /etc/postgresql/8.3/main/pg_hba.conf

and change the line

local all all #ident sameuser

into

local all all trust#ident sameuser

This might be a security issue on your system