i am getting following xml\[code\]<root xmlns="urn:schemas-microsoft-com:xml-diffgram-v1"><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity1" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="0"><StateID>1073</StateID><State>Ahmedabad</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity2" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="1"><StateID>1051</StateID><State>Amritsar</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity3" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="2"><StateID>1024</StateID><State>Bangalore</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity4" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="3"><StateID>1074</StateID><State>Bhopal</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity5" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="4"><StateID>1034</StateID><State>Chandigarh</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity6" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="5"><StateID>1025</StateID><State>Chennai</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity7" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="6"><StateID>1075</StateID><State>Dehradun</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity8" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="7"><StateID>1001</StateID><State>Delhi / NCR</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity9" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="8"><StateID>1062</StateID><State>Gwalior</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity10" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="9"><StateID>1011</StateID><State>Hyderabad</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity11" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="10"><StateID>1035</StateID><State>Jaipur</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity12" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="11"><StateID>1063</StateID><State>Jhansi</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity13" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="12"><StateID>1036</StateID><State>Jodhpur</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity14" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="13"><StateID>1064</StateID><State>Khajuraho</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity15" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="14"><StateID>1026</StateID><State>Kolkata</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity16" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="15"><StateID>1072</StateID><State>Ludhiana</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity17" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="16"><StateID>1010</StateID><State>Mumbai</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity18" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="17"><StateID>1065</StateID><State>Orchha</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity19" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="18"><StateID>1016</StateID><State>Pune</State></FromCity><FromCity xmlns="" xmlns:diffgr="urn:schemas-microsoft-com:xml-diffgram-v1" diffgr:id="FromCity20" xmlns:msdata="http://stackoverflow.com/questions/14059411/urn:schemas-microsoft-com:xml-msdata" msdata:rowOrder="19"><StateID>1037</StateID><State>Udaipur</State></FromCity></root>\[/code\]and following is my mapping\[code\]<class name="pkg.SourceCityWheelzResponse"> <description xmlns="">Default mapping for class GhraPayOrderRequest</description> <map-to xml="root" ns-prefix="diffgr" ns-uri="urn:schemas-microsoft-com:xml-diffgram-v1" /> <field name="fromCities" type="pkg.FromCity" collection="arraylist"> <bind-xml name="root:FromCity" node="element" xmlns:root="urn:schemas-microsoft-com:xml-diffgram-v1" /> </field> </class> <class name="pkg.FromCity"> <description xmlns="">Default mapping for class GhraPayOrderRequest</description> <map-to xml="FromCity" ns-prefix="diffgr" ns-uri="urn:schemas-microsoft-com:xml-diffgram-v1" /> <field name="stateId" type="java.lang.String" > <bind-xml name="FromCity:StateID" node="element" xmlns:FromCity="urn:schemas-microsoft-com:xml-diffgram-v1" /> </field> <field name="state" type="java.lang.String" > <bind-xml name="FromCity:State" node="element" xmlns:FromCity="urn:schemas-microsoft-com:xml-diffgram-v1"/> </field> </class>\[/code\]but i am getting following error\[code\]org.springframework.oxm.UnmarshallingFailureException: Castor unmarshalling exception; nested exception is org.exolab.castor.xml.MarshalException: The namespace associated with the prefix 'diffgr' could not be resolved. at org.springframework.oxm.castor.CastorMarshaller.convertCastorException(CastorMarshaller.java:675) at org.springframework.oxm.castor.CastorMarshaller.unmarshalDomNode(CastorMarshaller.java:554) at org.springframework.oxm.support.AbstractMarshaller.unmarshalDomSource(AbstractMarshaller.java:307) at org.springframework.oxm.support.AbstractMarshaller.unmarshal(AbstractMarshaller.java:125)\[/code\]Please help me to solve this