         if (children == null)
         {
             children = [];
-            var columns:Array = group.isNodeGroup() ? group.graph.source.nodeProperties : group.graph.source.edgeProperties;
+            var columns:Array = group.isNodeGroup() ? 
+                group.graph.source.nodeProperties.getSessionState() as Array :
+                group.graph.source.edgeProperties.getSessionState() as Array;
 
             for (var idx:int = columns.length - 1; idx >= 0; idx--)
             {


        private function translateReferences(idToKeyMappings:Object, values:Array):Array
        {
            return values.map(function(item) { return idToKeyMappings[item]; });
        }

        private function partitionElements(elements:Array, propertyName:String):Object

    import weave.api.data.IDataSource;
    import weave.api.data.IWeaveTreeNode;
    import weave.api.data.IColumnReference;
    import weave.api.data.IAttributeColumn;    
    import weave.api.data.IQualifiedKey; 
    import weave.api.getCallbackCollection;
    import weave.api.registerLinkableChild;
    import weave.api.newLinkableChild;
