function winopen(desturl,wname,w1,h1){
	var x0, y0;
	var w=600;
	var h=600;
	if (w1!='0') {w=w1}
	if (h1!='0') {h=h1}
	top.name="trotto";
	if (navigator.appVersion.charAt(0)>=3) {
		newwindow = open('', wname, 'toolbar=0,menubar=0,status=no,left=0,top=0,screenX='+x0+',screenY='+y0+',width='+w+',height='+h+',resizable=yes,scrollbars=yes,dependent=no');
		x0=(screen.availWidth-w)/2;
		y0=(screen.availHeight-h)/3;
		newwindow.moveTo(x0,y0);
		newwindow.focus();
		newwindow.location.replace(desturl);   
	}else{
		newwindow = open(desturl, wname, 'toolbar=0,menubar=0,status=no,left=0,top=0,screenX='+x0+',screenY='+y0+',width='+w+',height='+h+',resizable=yes,scrollbars=yes,dependent=no');
	}
}