[рони]

tai,

http://learn.javascript.ru/datetime

<script>
  var jqdate = '25.06.2014 12:20:00';
		var jqdates = jqdate.substr(-2);
		var jqdatem = jqdate.substr(-5, 2);
		var jqdateh = jqdate.substr(-8, 2);
    var d = new Date();
    var time = jqdate.replace(/^(\d+)\.(\d+)\./, '$2/$1/')
d.setTime(Date.parse(time));
d.setMinutes(d.getMinutes()+30)
document.write(d.toLocaleTimeString());
</script>