function popUp(url, name, popupWidth, popupHeight, focusNow, extra)
{
	if (screen.width  && screen.height) {
		w = screen.width;
		h = screen.height;
	} else  {
		w = popupWidth;
		h = popupHeight;
	}

	horizontalPosition = (w - popupWidth) / 2;
	verticalPosition = (h - popupHeight) / 2;		
	settings = "width=" + popupWidth + ",height=" + popupHeight + ",left=" + horizontalPosition + ",top=" + verticalPosition + "," + extra;
	popUpWindow = window.open(url, name, settings);

	if (focusNow == true){
		popUpWindow.focus();
	} else {
		document.focus();
	}
}