Event.observe(window, 'load', convert_times, false);

function convert_times()
{
	var e_list = document.getElementsByClassName('timestamp');
	var d = new Date();
	var offset = (d.getTimezoneOffset() * 60000);

	for(var i = 0; i < e_list.length; i++)
	{
		var d = new Date();
		d.setTime(Date.parse(e_list[i].innerHTML) - offset);
		new Insertion.After(e_list[i],d.formatDate('M j, Y H:i'))
		Element.remove(e_list[i])
	}
}