Can I pass an xml document as input into a MetaMatrix WebService?

Issue

• I have a procedure in MetaMatrix that call the Procedure in Oracle which accept an XML string as input. 

• I can execute the procedure in MetaMatrix by passing the xml string and enclosed it with single code ie.  '<xml....>' and it works fine. 

• When I create a WebService on top of the MetaMatrix procedure, I cannot execute the WebService at all.  If I put single quote around the string input<inputXML>'<ns.......>'</inputXML>, MetaMatrix cannot parse it and gives me an error at <.  If I don't put anything, I got an oracle error because it could not parse the xml string.