[Solved]-Highcharts add series dynamically-Highcharts

set for your yaxis:

yaxis: {
    type: 'datetime'
}

see fiddle

edit: timeline / zoom http://jsfiddle.net/dgdaf/5/

edit: use callback to add series, when chart is ready. however, why don't you add these series when chart is created?

    chart = new highcharts.chart(options, function(ch) {

        $.each(seriesoptions, function (itemno, item) {
            ch.addseries({                        
                name: item.name,
                data: item.data
            }, false);

        });
        chart.redraw();
    });