 		private const _proxyColumnToReferenceMap:Dictionary = new Dictionary(false);
 		
 		/**
-		 * dispose
 		 * This function should be called when the IDataSource is no longer in use.
 		 * All existing pointers to objects should be set to null so they can be garbage collected.
 		 */

			{
				debug('requestColumnFromSource', request.columnReference.getHashCode());
				
				//StageUtils.callLater(this, requestColumnFromSource, [request.columnReference, request.proxyColumn]);
				requestColumnFromSource(request.columnReference, request.proxyColumn);
			}
			else
			{

		/* abstract */ protected function requestHierarchyFromSource(subtreeNode:XML = null):void { }

		/**
		 * This function must be implemented by classes that extend AbstractDataSource.
		 * This function should make a request to the source to fill in the proxy column.
		 * @param columnReference An object that contains all the information required to request the column from this IDataSource. 
