Google Map V3 – Allow only one infobox to be displayed at a time

Change this part:

        google.maps.event.addListener(marker, "click", function (e) {
            ib.open(map, this);
        });

        var ib = new InfoBox(myOptions);

       google.maps.event.addListener(marker2, "click", function (e) {
            ib2.open(map, this);
        });

        var ib2 = new InfoBox(myOptions2);

to the following:

    var ib = new InfoBox();

    google.maps.event.addListener(marker, "click", function (e) {
        ib.close();
        ib.setOptions(myOptions)
        ib.open(map, this);
    });

   google.maps.event.addListener(marker2, "click", function (e) {
        ib.close();
        ib.setOptions(myOptions2)
        ib.open(map, this);
    });

Works for me, also in IE9: http://jsfiddle.net/doktormolle/9jhAy/1/

Note the use of ib.close() before opening the infoBox, seems to be the trick.