Client API problem

[Fan, Jan-fon]

Hi,
I am using AXIS2C client api in my application to access web services which is 
developed with .NET.
The way that I send my request is as below:

    /* Send request */
    ret_node = axis2_svc_client_send_receive(svc_client, env, payload);

    if (ret_node)
    {
        axis2_char_t *om_str = NULL;
        om_str = axiom_node_to_string(ret_node, env);
        if (om_str)
            printf("\nReceived OM : %s\n", om_str);
        printf("\nclient invoke SUCCESSFUL!\n");

        AXIS2_FREE(env->allocator, om_str);
        ret_node = NULL;
    }
    else
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
                        "Stub invoke FAILED: Error code:" " %d :: %s",
                        env->error->error_number,
                        AXIS2_ERROR_GET_MESSAGE(env->error));
        printf("client invoke FAILED!\n");
        }

I have 2 questions:
1. I send my requests in a loop. Inside the loop, I keep sending about 30 
requests to the same web service. Sometime one or more requests would print out 
"client  invoke FAILED". What could be the reason that causes this problem?

2. Sometime when I print out the result from server, it only contain partial 
information.


Really appreciate your help!

Jan-fon