//öppnar ett centrerat fönster --------------------------------
var popUpWin=0;
function popup(URL,winName,width,height)
{
  if(popUpWin)
  {
    if(!popUpWin.closed) popUpWin.close();
  }

	if (parseInt(navigator.appVersion) >= 3){
		if (navigator.appName == "Netscape" && parseInt(navigator.appVersion)<5){
			var tools = new Packages.java.awt.Toolkit.getDefaultToolkit();
			screen=tools.getScreenSize();
		}
		x = screen.width;
		y = screen.height;
	}
	popUpWin = open(URL,winName,'top=' + parseInt(y/2-height/2-16) + ',left=' + parseInt(x/2-width/2-5) + ',width=' + width + ',height=' + height + ',scrollbars=yes,resizable=yes');
	popUpWin.focus();
}