Newbie here! Cannot connect to my jabber server, except with one client (Jabbear) - Pidgin fails

I am very new to this, so please bear with my lack of knowledge!

I have installed ejabberd 2.1.5 on my Linux server (32 bit, from a binary). I set it up as prescribed on the guide and have an admin user. I can connect to the web management interface fine.

When I try to log in from a client I get a connection closed. This has happened with Pidgin on a Windows machine and a Linux machine, and also my Nokia N900 (its own messaging client).

I downloaded and installed Jabbear and as long as the secure authentication is set to off I can connect just fine. Both the admin account and a basic test one log in without problems and I have set statuses and added each "buddy" to the other account.

Running the server over SSH in LIVE mode, I get the following upon a successful connection:

=INFO REPORT==== 11-Aug-2010::03:36:40 ===
I(<0.352.0>:ejabberd_listener:232) : (#Port<0.458>) Accepted connection {{xxx,xxx,xxx,xxx},51919} -> {{yyy,yyy,yyy,yyy},5222}

=INFO REPORT==== 11-Aug-2010::03:36:41 ===
I(<0.394.0>:ejabberd_c2s:716) : ({socket_state,gen_tcp,#Port<0.458>,<0.393.0>}) 
    Accepted authentication for testing by ejabberd_auth_internal

=INFO REPORT==== 11-Aug-2010::03:36:41 ===
I(<0.394.0>:ejabberd_c2s:839) : ({socket_state,gen_tcp,#Port<0.458>,<0.393.0>}) 
    Opened session for testing@-------.com/jabbear1

When it fails, the following message is shown:

=ERROR REPORT==== 11-Aug-2010::03:30:37 ===
** State machine <0.373.0> terminating
** Last event in was {xmlstreamelement,
                         {xmlelement,"starttls",
                             [{"xmlns","urn:ietf:params:xml:ns:xmpp-tls"}],
                             []}}
** When State == wait_for_feature_request
**      Data  == {state,{socket_state,gen_tcp,#Port<0.435>,<0.372.0>},
                        ejabberd_socket,#Ref<0.0.0.9823>,false,"1258971306",
                        {sasl_state,"jabber","-------.com",[],
                                    #Fun,
                                    #Fun,
                                    #Fun,undefined,
                                    undefined},
                        c2s,c2s_shaper,false,true,false,false,
                        [verify_none,
                         {certfile,"/opt/ejabberd-2.1.5/conf/server.pem"}],
                        false,undefined,[],"--------.com",[],undefined,
                        {pres_t,0},
                        {pres_f,0},
                        {pres_a,0},
                        {pres_i,0},
                        undefined,undefined,undefined,false,
                        {userlist,none,[],false},
                        unknown,unknown,
                        {{86,30,140,52},51851},
                        []}
** Reason for termination =
** {{case_clause,{error,{open_error,-10}}},
    [{tls,tcp_to_tls,2},
     {ejabberd_socket,starttls,3},
     {ejabberd_c2s,wait_for_feature_request,2},
     {p1_fsm,handle_msg,10},
     {proc_lib,init_p,5}]}

There is also an error on startup:

Erlang (BEAM) emulator version 5.6.4 [source] [smp:4] [async-threads:0] [kernel-poll:true]

Eshell V5.6.4  (abort with ^G)
(ejabberd@localhost)1>
=ERROR REPORT==== 11-Aug-2010::03:24:38 ===
C(<0.41.0>:sha:49) : unable to load driver '/opt/ejabberd-2.1.5/lib/ejabberd-2.1.5/priv/linux-x86/lib/sha_drv.so': libssl.so.0.9.8: 
   cannot open shared object file: No such file or directory

=INFO REPORT==== 11-Aug-2010::03:24:38 ===
I(<0.41.0>:ejabberd_app:70) : ejabberd 2.1.5 is started in the node ejabberd@localhost

I'm a bit stumped to be honest! I have tried turning off secure authentication on Pidgin and my phone and it still fails. I get the exact same error message when I try to connect with Jabbear WITH secure authentication switched on so something there seems to be causing a hiccup and also Pidgin/N900 clients are perhaps not actually switching off secure authentication.

I'd be really grateful if anyone could help - I'm sure this is something silly I've not realised, as I said I'm quite new to this and whilst I can SSH in and set this up in a shell, I am not really very experienced with *nix either.

Thanks! :)