var tDiff = -1;
	var tActive = null;
	var $validtyWarnerDiv = $("#validtyWarnerDiv");
	var updValidity = function()
	{
		var mNow = Math.floor((new Date()).getTime() / 1000/60);
		var minutesLeft = (validUntil - mNow + tDiff);
		var res = "";
		if(minutesLeft <= 1)
		{
			res = "<img src=\"img/validity-warning.png\" style=\"margin-right: 1em; vertical-align: middle;\"> Achtung, Preise werden demnächst oder sind ungültig.";
			window.clearInterval(tActive);
		
		} else
		{
			res = "Die Preise sind noch mindestens";
			var hours = Math.floor(minutesLeft / 60);
			if(hours>0)
			{
				res += " " + hours + " Stunde";
				if(hours > 1)
				{
					res += "n";
				}
				minutesLeft -= hours*60;
			}
			if(minutesLeft > 0)
			{
				if(hours>0)
				{
					res += " und"
				}
				res += " " + minutesLeft + " Minute";
				if(minutesLeft > 1)
				{
					res += "n";
				}
			}
			res += " gültig.";
		
		}
		$validtyWarnerDiv.html(res);
	};
	$.ajax ({ url: "/small-file.html", type:"GET",dataType:"text", cache:false
		, complete: function(r,s) { if(r.status == 200) 
		{
			tDiff = Math.floor(((new Date()).getTime() - (new Date(r.getResponseHeader("Date"))).getTime() )/1000/60);
			updValidity();
			tActive = window.setInterval(updValidity, 30*1000);
		}
	}});