function BrowserValidator()
{
	var agent = navigator.userAgent.toLowerCase();
	var isWindows = (agent.indexOf("win")!=-1)?true:false;
	var isMac = (agent.indexOf("mac")!=-1)?true:false;
	var isIE5up = (document.getElementById && agent.indexOf("msie")!=-1);
	var isIE55up = (document.getElementById && agent.indexOf("msie")!=-1 && agent.indexOf("msie 5.0")==-1);
	var isNN6up = (document.getElementById && agent.indexOf("netscape")!=-1)?true:false;
	
	this.isIE = (document.all && agent.indexOf("msie")!=-1)?true:false;
	this.isNN = isNN6up;
	
	if ((isIE5up || isNN6up) && isWindows) this.IsValidBrowser = true;
	else this.IsValidBrowser = false;
}
var thisBrowser = new BrowserValidator();
//if (!thisBrowser.IsValidBrowser) alert("It's not a valid browser!");