mechanism not supported error calling sasl_client_start()

[Ted Yu]

Hi,
I installed cyrus-sasl-2.1.26

    rc = sasl_client_new(service_name, /* The service we are using*/

        host_name_.c_str(),

        NULL, NULL, /* Local and remote IP address strings

                          (NULL disables mechanisms which require this
info)*/

        NULL, /*connection-specific callbacks*/

        0 /*security flags*/, &sconn_);

    sasl_security_properties_t *props = new sasl_security_properties_t();

    ::memset(props, 0, sizeof(sasl_security_properties_t));

    props->max_ssf = 2;

    sasl_setprop(sconn_, SASL_SEC_PROPS, (void *)props);

    const char *mechusing, *mechlist = "GSSAPI";

      currentReturnCode = sasl_client_start(sconn_, /* the same context
from above */

           mechlist, /* the list of mechanisms

            from the server */

            NULL, /* filled in if an

            interaction is needed */

            &out, /* filled in on success */

            &outlen, /* filled in on success */

            &mechusing);

Return value from sasl_client_new() was SASL_OK

The return value from sasl_client_start() was -4.

Can someone tell me whether I missed any parameter(s) ?