diff --git a/htdocs/samples/timeseries_date.html b/htdocs/samples/timeseries_date.html
index 475d10c..ceb8e2f 100644
--- a/htdocs/samples/timeseries_date.html
+++ b/htdocs/samples/timeseries_date.html
@@ -14,7 +14,7 @@
           x : 'x',
           xFormat : '%Y%m%d',
           columns: [
-            ['x', new Date('2013-01-01 00:00:00'), new Date('2013-01-02 00:00:00'), new Date('2013-01-03 00:00:00'), new Date('2013-01-04 00:00:00'), new Date('2013-01-05 00:00:00'), new Date('2013-01-06 00:00:00')],
+            ['x', new Date('2013-01-01T00:00:00Z'), new Date('2013-01-02T00:00:00Z'), new Date('2013-01-03T00:00:00Z'), new Date('2013-01-04T00:00:00Z'), new Date('2013-01-05T00:00:00Z'), new Date('2013-01-06T00:00:00Z')],
             ['sample', 30, 200, 100, 400, 150, 250],
             ['sample2', 130, 300, 200, 450, 250, 350]
           ]
@@ -52,7 +52,7 @@
       setTimeout(function () {
         chart.load({
           columns: [
-            ['x', new Date('2014-01-02 00:00:00'), new Date('2014-02-02 00:00:00'), new Date('2014-03-02 00:00:00'), new Date('2014-04-02 00:00:00'), new Date('2014-05-02 00:00:00'), new Date('2014-06-02 00:00:00')],
+            ['x', new Date('2014-01-02T00:00:00Z'), new Date('2014-02-02T00:00:00Z'), new Date('2014-03-02T00:00:00Z'), new Date('2014-04-02T00:00:00Z'), new Date('2014-05-02T00:00:00Z'), new Date('2014-06-02T00:00:00Z')],
             ['sample', 500, 630, 690, 440, 630, 900],
             ['sample2', 400, 600, 460, 200, 350, 450]
           ]