$("form.mailster-form.mailster-form-submit.mailster-ajax-form.mailster-form-4 select#mailster-assunto-select-4").change(function(){
var select = $(this).children("option:selected").val();
$('form.mailster-form.mailster-form-submit.mailster-ajax-form.mailster-form-4').attr('name', select);
});