I am trying to add a new user in moodle via webservice with custom fields

I am trying to create a user in moodle via webservice .The user is created successfuly but the custom field is not filled.Can anybody redirect me towards the solution?In custom field i am trying to send value for gender as male. $functionName = 'core_user_create_users'; $user1 = new stdClass(); $user1->username = $form_state['values']['UserName']; $user1->password=$form_state['values']['PassWord']; $user1->firstname = $form_state['values']['FirstName']; $user1->lastname = $form_state['values']['LastName']; $user1->email = $form_state['values']['Emailid']; $user1->mailformat = '0'; $preferencename1 = 'auth_forcepasswordchange'; $user1->preferences = array( array('type' => $preferencename1, 'value' => 'true') ); $user1->customfields = array( array('type' => 'Gender', 'value' => 'Male') ); $users = array($user1); $params = array('users' => $users); /// REST CALL $rest_format = 'json'; //$server_url = $domain_name . '/webservice/rest/server.php' . '?wstoken=' . $token . '&wsfunction=' . $function_name; $server_url = 'localhost/moodle' . '/webservice/rest/server.php'. '?wstoken=' . '7525ce057d455657a4e83d7aa63f3684' .'&wsfunction='. $functionName; require_once('curl.inc'); $curl = new curl; $rest_format = ($rest_format == 'json') ? '&moodlewsrestformat=' . $rest_format : ''; $resp =$curl->post($server_url.$rest_format , $params); dpm($resp); $res=json_decode($resp); dpm($res);