column.setAggregateOn( groupName );
if ( ExpressionUtil.hasAggregation( column.getExpression( ) ) ) column.setAggregateOn( groupName );
	public void addCachedListToListing( List columns, List tmpList,			GroupElement group, String groupName )	{		for ( int j = 0; j < columns.size( ); j++ )		{			ComputedColumn column = (ComputedColumn) columns.get( j );			if ( !tmpList.contains( column ) )			{				column.setAggregateOn( groupName );				tmpList.add( column );			}		}	}