function popUp(u,w,h) {
// pops open a popup window
        if (window.popWin && !popWin.closed) {
                if (popWin.resizeTo) {
                        popWin.resizeTo(w,h);
                } else {
                        popWin.outerWidth = w;
                        popWin.outerHeight = h;
                }
                popWin.location = u;
                popWin.focus();
        } else {
                popWin = window.open(u,'pop','width='+w+',height='+h);
                popWin.opener = window;
        }
}

function popDown() {
// closes the popup when this window regains focus
// call in the body tag onFocus event
        if (window.popWin) {
                popWin.close();
        }
}