function openWindow(filename, winname, width, height, feature) {
	var features, top, left;
	var reOpera = /opera/i ;
	var winnameRequired = ((navigator.appName == "Netscape" && parseInt(navigator.appVersion) == 4) || reOpera.test(navigator.userAgent));
	
	left = (window.screen.width - width) / 2;
	top = (window.screen.height - height) / 2;	
	if(feature == '')
		features = "width=" + width + ",height=" + height + ",top=" + top + ",left=" + left;
	else
		features = "width=" + width + ",height=" + height + ",top=" + top + ",left=" + left + "," + feature;
	//if(!winnameRequired)	winname = "";
	void(window.open(filename,winname,features));
}