I think there might be another way to convert the data into xml (although it is a bit unconventional. If the records are hierarchical you can use the shaped recordset provider to maintain the parent child relationship, if not, just query as normal. Once you have the recordset populated, you can persist it into xml. Check out my article at:
http://www.sqlservercentral.com/columnists/jwiner/shapexml.asp It should tell you exactly how to do it. Hope that helps.