how to configure the hostname with the authentication

Hi
I am a newbie and I have trying to configure ejabberd for more that I can even remember...

The problems:
I want to use the hostname of my host as the parameter for host and when I launch it, it stops complaining about the authentication.

S2# killall epmd
No matching processes were found
S2# erl -pa /usr/local/lib/erlang/ejabberd/ebin -name S2 -s ejabberd -ejabberd config \"/usr/local/etc/ejabberd/ejabberd.cfg2\" Erlang (BEAM) emulator version 5.5 [source] [async-threads:0] [hipe] [kernel-poll:false]
...
=PROGRESS REPORT==== 14-Jun-2006::11:48:47 ===
supervisor: {local,ejabberd_sup}
started: [{pid,<0.177.0>},
{name,ejabberd_listener},
{mfa,{ejabberd_listener,start_link,[]}},
{restart_type,permanent},
{shutdown,infinity},
{child_type,supervisor}]

=CRASH REPORT==== 14-Jun-2006::11:48:47 ===
crasher:
pid: <0.41.0>
registered_name: []
error_info: {bad_return,{{ejabberd_app,start,[normal,[]]},
{'EXIT',{undef,
[{ejabberd_auth_undefined,
start,
["S2.labo4g.rennes.enst-bretagne.fr"]},
{lists,foreach,2},
{ejabberd_app,start,2},
{application_master,start_it_old,4}]}}}}

I have the following file

% $Id: ejabberd.cfg.example 538 2006-04-22 04:02:42Z alexey $

%override_acls.
override_global.
override_local.
override_acls.

% Users that have admin access. Add line like one of the following after you
% will be successfully registered on server to get admin access:
%{acl, admin, {user, "aleksey"}}.
%{acl, admin, {user, "ermine"}}.
%{acl, admin, {user, "admin"}}.
{acl, admin, {user, "admin", "labo4g.rennes.enst-bretagne.fr"}}.
%{acl, admin, {user, "admin", "localhost"}}.

% Blocked users:
%{acl, blocked, {user, "test"}}.

% Local users:
{acl, local, {user_regexp, ""}}.

% Another examples of ACLs:
%{acl, jabberorg, {server, "jabber.org"}}.
%{acl, aleksey, {user, "aleksey", "jabber.ru"}}.
%{acl, test, {user_regexp, "^test"}}.
%{acl, test, {user_glob, "test*"}}.

% Only admins can use configuration interface:
{access, configure, [{allow, admin}]}.

% Every username can be registered via in-band registration:
% You could replace {allow, all} with {deny, all} to prevent user from using
% in-band registration
{access, register, [{allow, all}]}.

% After successful registration user will get message with following subject
% and body:
{welcome_message,
{"Welcome!",
"Welcome to Jabber Service. "
"For information about Jabber visit http://jabber.org"}}.
% Replace them with 'none' if you don't want to send such message:
%{welcome_message, none}.

% List of people who will get notifications about registered users
%{registration_watchers, ["admin1@localhost",
% "admin2@localhost"]}.

% Only admins can send announcement messages:
{access, announce, [{allow, admin}]}.

% Only non-blocked users can use c2s connections:
{access, c2s, [{deny, blocked},
{allow, all}]}.

% Set shaper with name "normal" to limit traffic speed to 1000B/s
{shaper, normal, {maxrate, 1000}}.

% Set shaper with name "fast" to limit traffic speed to 50000B/s
{shaper, fast, {maxrate, 50000}}.

% For all users except admins used "normal" shaper
{access, c2s_shaper, [{none, admin},
{normal, all}]}.

% For all S2S connections used "fast" shaper
{access, s2s_shaper, [{fast, all}]}.

% Admins of this server are also admins of MUC service:
{access, muc_admin, [{allow, admin}]}.

% All users are allowed to use MUC service:
{access, muc, [{allow, all}]}.

% This rule allows access only for local users:
{access, local, [{allow, local}]}.

% Authentication method. If you want to use internal user base, then use
% this line:
{auth_method, internal}.

% For LDAP authentication use these lines instead of above one:
%{auth_method, ldap}.
%{ldap_servers, ["localhost"]}. % List of LDAP servers
%{ldap_uidattr, "uid"}. % LDAP attribute that holds user ID
%{ldap_base, "dc=example,dc=com"}. % Search base of LDAP directory
%{ldap_rootdn, "dc=example,dc=com"}. % LDAP manager
%{ldap_password, "******"}. % Password to LDAP manager

% For authentication via external script use the following:
%{auth_method, external}.
%{extauth_program, "/path/to/authentication/script"}.

% For authentication via ODBC use the following:
%{auth_method, odbc}.
%{odbc_server, "DSN=ejabberd;UID=ejabberd;PWD=ejabberd"}.

% Host name:
%{hosts, ["localhost"]}.
{hosts, ["S2.labo4g.rennes.enst-bretagne.fr"]}.
{host_config, "S2.labo4g.rennes.enst-bretagne.fr", [{auth_method, internal}]}.

%% Anonymous login support:
%% auth_method: anonymous
%% anonymous_protocol: sasl_anon|login_anon|both
%% allow_multiple_connections: true|false
%%{host_config, "public.example.org", [{auth_method, anonymous},
%% {allow_multiple_connections, false},
%% {anonymous_protocol, sasl_anon}]}.
%% To use both anonymous and internal authentication:
%%{host_config, "public.example.org", [{auth_method, [anonymous, internal]}]}.

% Default language for server messages
{language, "en"}.

% Listened ports:
{listen,
[{5222, ejabberd_c2s, [{access, c2s}, {shaper, c2s_shaper},
{max_stanza_size, 65536},
starttls, {certfile, "/usr/local/etc/server.pem"}]},
{5223, ejabberd_c2s, [{access, c2s},
{max_stanza_size, 65536},
tls, {certfile, "./ssl.pem"}]},
% Use these two lines instead if TLS support is not compiled
%{5222, ejabberd_c2s, [{access, c2s}, {shaper, c2s_shaper}]},
%{5223, ejabberd_c2s, [{access, c2s}, ssl, {certfile, "/usr/local/etc/server.pem"}]},
{5269, ejabberd_s2s_in, [{shaper, s2s_shaper},
{max_stanza_size, 131072}
]},
{5280, ejabberd_http, [http_poll, web_admin]},
{8888, ejabberd_service, [{access, all},
{hosts, ["icq.localhost", "sms.localhost"],
[{password, "secret"}]}]}
]}.

% Use STARTTLS+Dialback for S2S connections
{s2s_use_starttls, true}.
{s2s_certfile, "/usr/local/etc/server.pem"}.
%{domain_certfile, "example.org", "./example_org.pem"}.
%{domain_certfile, "example.com", "./example_com.pem"}.

% If SRV lookup fails, then port 5269 is used to communicate with remote server
{outgoing_s2s_port, 5269}.

% Used modules:
{modules,
[
{mod_register, [{access, register}]},
{mod_roster, []},
{mod_privacy, []},
{mod_adhoc, []},
{mod_configure, []}, % Depends on mod_adhoc
{mod_configure2, []},
{mod_disco, []},
{mod_stats, []},
{mod_vcard, []},
{mod_offline, []},
{mod_announce, [{access, announce}]}, % Depends on mod_adhoc
{mod_echo, [{host, "echo.localhost"}]},
{mod_private, []},
{mod_irc, []},
% Default options for mod_muc:
% host: "conference." ++ ?MYNAME
% access: all
% access_create: all
% access_admin: none (only room creator has owner privileges)
{mod_muc, [{access, muc},
{access_create, muc},
{access_admin, muc_admin}]},
% {mod_muc_log, []},
% {mod_shared_roster, []},
{mod_pubsub, []},
{mod_time, []},
{mod_last, []},
{mod_version, []}
]}.

Thanks for any help

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