var jm;

function popUp(jm) {
	var iMyWidth;
	var iMyHeight;
	//gets top and left positions based on user's resolution so hint window is centered.
	iMyWidth = (window.screen.width/2) - (195 + 10); //half the screen width minus half the new window width (plus 5 pixel borders).
	iMyHeight = (window.screen.height/2) - (225 + 50); //half the screen height minus half the new window height (plus title and status bars).

if (jm != null) {
var win2 = window.open( jm + "impressum/index.html","Window2","height=450,width=390,resizable=no,left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight + ",scrollbars=no");
}
else{
var win2 = window.open("impressum/index.html","Window2","height=450,width=390,resizable=no,left=" + iMyWidth + ",top=" + iMyHeight + ",screenX=" + iMyWidth + ",screenY=" + iMyHeight + ",scrollbars=no");
}
win2.focus();
}