1. Edit pg_hba.conf

# "local" is for Unix domain socket connections only
local   all         all                               trust
# IPv4 local connections:
host    all         all         127.0.0.1/32          md5
host    all         all         192.168.1.0 255.255.255.0       md5
# IPv6 local connections:
#host    all         all         ::1/128               trust

2. Edit postgres.conf

55
56 listen_addresses = '*' # what IP address(es) to listen on;
57 # comma-separated list of addresses;
58 # defaults to 'localhost', '*' = all
59 # (change requires restart)

4. For CentOS5.1, create symbolic links:
ln -s /usr/local/lib/libproj.so.0 /usr/lib/libproj.so.0
ln -s /usr/local/lib/libgeos_c.so.1 /usr/lib/libgeos_c.so.1
ldconfig
/etc/init.d/postgresql stop
/etc/init.d/postgresql start

3. Postgis Post Install

createdb -E utf8 template_routing
createlang plpgsql template_routing
psql -d template_routing -f /usr/share/postgresql-8.3-postgis/lwpostgis.sql 
psql -d template_routing -f /usr/share/postgresql-8.3-postgis/spatial_ref_sys.sql 
psql -d template_routing -f /usr/share/postlbs/routing_core.sql 
psql -d template_routing -f /usr/share/postlbs/routing_core_wrappers.sql