XMLTYPE.toObject causes a ORA-01722:invalid number error message in 10g

 Hi,

I have a problem in Oracle 10g(10.2.0.2.3) while using the  XMLTYPE.toObject function ,but same thing is working fine in Oracle 9i.

declare
l_obj EDI855_T;
l_xml xmltype;

begin

    SELECT xmltype(xml)  INTO l_xml
      FROM xxxml_test_table
     WHERE process_nm = 'EDI855'
       AND status_cd = 'P'
       AND record_no = p_record_no;

    l_xml.toobject(l_obj, 'EDI855', 'PurchaseOrder');
end;

In the above program the l_xml.toobject is failing , I am getting the ora-01722:invalid number.

Highly appreciate if any one provide the solution.