Dynamic Value Columns erasing X-Axis labels

I am dynamically altering the columns of an iChart in javascript. After the chart updates, the X-Axis labels disappear. Any ideas?

document.getElementById("InventoryChart").getChartObject().setValueColumns(output);

document.getElementById("InventoryChart").updateChart(true);

document.getElementById("InventoryChart").refresh();

Edited by: tsander on Jul 9, 2010 10:34 PM