Can't get Ejabberd to work on Debian Sarge - HAYELP!

I've had an installation of Ejabberd with JWChat working on the same machine under (I think) Debian Woody... BUT I had to rebuild the server (after I broke it installing egroupware... but that's another story)..

So, having remembered that Ejabberd was a nice and easy install I thought, come back here, follow the install tutorial and it should be nice...

No such joy...

I've followed the tutorial to the letter, but I can't get into ejabberd or jwchat at all..

I can stop and start the server nicely, I can check on the status, using ejabberctl status.

BUT I can't register a user, or get into webadmin...

If I try registering a user I get this:

ukec4deb1:/etc/apache2# ejabberdctl --node ejabberd@ukec4deb1 register argon0 jabber.crystaleu.net argon0
Can't register user "argon0@jabber.crystaleu.net" at node ejabberd@ukec4deb1: 
  {'EXIT',
    {badarg,
      [{erlang,
        port_control,
        [stringprep_port,1,"jabber.crystaleu.net"]},
       {stringprep,control,2},
       {jlib,nameprep,1},
       {ejabberd_auth,try_register,3},
       {rpc,'-handle_call/3-fun-0-',6}]}}

My ejabberd.cfg file is below. My server is called ukec4deb1, on the uk.crystaleu.net domain. I have set up a hosts entry for jabber.crystaleu.net for this machine.

Any Ideas anyone?

% Default Debian ejabberd.cfg

%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, "argon0"}}.

% 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:
{access, register, [{allow, all}]}.

% None username can be registered via in-band registration:
%{access, register, [{deny, all}]}.

% After successful registration user will get message with following subject
% and body:
{welcome_message,
 {"Welcome!",
  "Welcome to Debian 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(s) name: (replace for your hostname(s))
% Old {host, "localhost"}. option is equivalent to {hosts, ["localhost"]}.
{hosts, ["localhost", "jabber.crystaleu.net"]}.


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

% Listened ports:
{listen,

 [{5222, ejabberd_c2s,     [{access, c2s},
                            starttls, {certfile, "/etc/ssl/certs/ejabberd.pem"},
                            {shaper, c2s_shaper}]},


  {5223, ejabberd_c2s,     [{access, c2s},
                            tls, {certfile, "/etc/ssl/certs/ejabberd.pem"},
			    {shaper, c2s_shaper}]},


  {5269, ejabberd_s2s_in,  [{shaper, s2s_shaper}]},


  {5280, ejabberd_http,    [http_poll, web_admin]}
 ]}.

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

% Used modules:
{modules,
 [
  {mod_announce,   [{access, announce}]},
  {mod_register,   [{access, register}]},
  {mod_roster,     []},
  {mod_shared_roster, []},
  {mod_privacy,    []},
  {mod_configure,  []},
  {mod_configure2, []},
  {mod_disco,      [{extra_domains, ["users.jabber.org"]}]},
  {mod_stats,      []},
  {mod_vcard,      []},
  {mod_offline,    []},
  {mod_echo,       []},
  {mod_private,    []},
  {mod_irc,        []},

  {mod_muc,        [{access, muc},
		    {access_create, muc},
		    {access_admin, muc_admin}]},
  {mod_pubsub,     []},
  {mod_time,       []},
  {mod_last,       []},
  {mod_version,    []}
 ]}.