problems with mod_xmlrpc

i recently installed xmerl 0.20, xml-rpc-Erlang 1.13 and finally mod_xmlrpc to my ejabberd installation.
the xml-rpc-server is now up and seems to run fine. but if a XML-RPC-Request comes in, following error will occur and will return nothing to the xml-rpc-client:

=CRASH REPORT==== 11-Aug-2006::05:48:50 ===
  crasher:
    pid: <0.410.0>
    registered_name: []
    error_info: {badarg,[{xmlrpc_decode,decode_params,1},
                          {xmlrpc_decode,decode_element,1},
                          {xmlrpc_decode,payload,1},
                          {xmlrpc_http,handle_payload,5},
                          {tcp_serv,start_session,3},
                          {proc_lib,init_p,5}]}
    initial_call: {tcp_serv,start_session,
                           [<0.258.0>,
                            {xmlrpc_http,
                                handler,
                                [50,{mod_xmlrpc,handler},started]},
                            #Port<0.332>]}
    ancestors: [<0.258.0>,<0.41.0>]
    messages: []
    links: [<0.258.0>,#Port<0.724>]
    dictionary: []
    trap_exit: false
    status: running
    heap_size: 987
    stack_size: 21
    reductions: 1471
  neighbours:

i'm new to erlang. i'm not sure if this error means, that the count of arguments to "handler" in xmlrpc_http is wrong?! did i get the wrong xmlrpc_http-version maybe?

xmlrpc_http.erl says:

-export([handler/4]).

[..]

%% Exported: handler/3

handler(Socket, Timeout, Handler, State) ->
    case parse_request(Socket, Timeout) of
        {ok, Header} ->
            ?DEBUG_LOG({header, Header}),
            handle_payload(Socket, Timeout, Handler, State, Header);
        {status, StatusCode} ->
            send(Socket, StatusCode),
            handler(Socket, Timeout, Handler, State);
        {error, Reason} -> {error, Reason}
    end.

this will export the function with 4 arguments, comment says 3, but actually has 4 arguments?

maybe anyone can help me with my problem.

thanks.

flip