Export a previous revision of an Item using SDK

We're using the SDK to generate a PDX package for Items, using the code below.  What we have works for the current revision of an Item, but we'd like to have the option to export a previous revision.  Is this possible using the SDK?

IItem item = (IItem)session.getObject(IItem.OBJECT_TYPE, "PART12345");

IDataObject[] exportObjects = {item};

String[] filters = {"Default Item Filter"};

IExportManager em = (IExportManager)session.getManager(IExportManager.class);

byte[] exportData = em.exportData(exportObjects, ExportConstants.EXPORT_FORMAT_PDX, filters);

Thanks in advance,
Drew