debian unstable postgresql-8.3 installation problem

["jeffry s" <paragasu@gmail.com>]

i am using debian unstable with gnome desktop.
but i failed to install postgresql package. this is the error message

Starting PostgreSQL 8.3 database server: main* Error: Could not create log file /var/log/postgresql/postgresql-8.3-main.log failed!

doing ls /var/log output

drwxrwxr-t 2 root        postgres      4096 2008-02-15 20:45 postgresql

anyone know how to fix this problem?