function isUndefined(v) {
    var undef;
    return v===undef;
}

function raw_popup(url, target, features) {
    if (isUndefined(target  )) target   = '_blank';
    if (isUndefined(features)) {
        var theWindow = window.open(url, target);
    } else {
        var theWindow = window.open(url, target, features);
        }
    theWindow.focus();
    return theWindow;
}