function popup(url)
{
	var h,w,x,y;
	
    w = 998;
	h = 710;
	
	x = screen.availWidth/2-w/2;
    y = screen.availHeight/2-h/2;
		
	fenster = window.open(url,"RenaultGrimm","status=no,directories=no,location=no,menubar=yes,toolbar=no,status=no,scrollbars=yes,screenX="+x+",screenY="+y+",width=" + w + ",height=" + h);
	 
	fenster.focus();
    return false;
}