You can override the $.fn.datetimebox.defaults.buttons to custom their behaviors.
<script type="text/javascript">
$.fn.datetimebox.defaults.buttons[0] = {
text: function(target){return $(target).datetimebox('options').currentText;},
handler: function(target){
var opts = $(target).datetimebox('options');
$(target).datetimebox('setValue', opts.formatter.call(target, new Date()));
$(target).datetimebox('hidePanel');
}
}
</script>