Problem to restart postgresql services

hello Sir
i have install postgresql-server-8.1.11 and postgresql-8.1.11
and
create owner as fellow

-bash-3.2$ createuser -P
Enter name of role to add: asterisk
Enter password for new role:
Enter it again:
Shall the new role be a superuser? (y/n) n
Shall the new role be allowed to create databases? (y/n) y
Shall the new role be allowed to create more new roles? (y/n) n
CREATE ROLE

and change in file /var/lib/pgsql/data/postgresql.conf
as
tcpip_socket = true max_connections = 100
# note: increasing max_connections costs about 500 bytes of shared
# memory per connection slot, in addition to costs from shared_buffers
# and max_locks_per_transaction.
#superuser_reserved_connections = 2
port = 5432

and in /var/lib/pgsql/data/pg_hba.conf

host all asterisk 127.0.0.1 255.255.255.255 md5
local all asterisk trust

then create database as
-bash-3.2$ createdb --owner=asterisk asterisk
CREATE DATABASE
and then
exit
when i restart services

[root@localhost ~]# service postgresql restart
i got
Stopping postgresql service: [ OK ]
Starting postgresql service: [FAILED]

what is the problem
please help me
Regards:
shiv