live data problem

Hi
I have be working to create a org chart for a company I want the data to be live coming from the database to the chart. I have tried a number of different way to do this and every thing the org chart dose not like the way the xml is been passed to it. This is the code I am work on :

<mx:XML source="http://portaldev.adtest.com/pls/coreportal20/cp_org_chart_api.create_org_chart_xml"
id="OrgChartGML"/>

<mx:HTTPService id="treeData" url="http://portaldev.adtest.com/pls/coreportal20/cp_org_chart_api.create_org_tree_xml" resultFormat="e4x" result="resultHandler(event)" />

I have the tree data updating once you refresh the page by using a httpservice but when I try pass the data for the org chart by using a httpservice it will not read the xml because there in no root data in the chart.

if any one could help it would be grate

Thanks
Paula