100分求解AxisFault问题，求救大家，结果出来了，但有错误提示？？

Question

运行能出现结果，也正确，但有提示！客户段程序如下：
import java.sql.*;
import org.apache.axis.client.Call;
import org.apache.axis.client.Service;
import javax.xml.namespace.QName;
import javax.xml.rpc.ServiceException;
import java.net.MalformedURLException;
import java.rmi.RemoteException;public class Saysql {
    public static void main(String[] args) 
{
SqlExam say = new SqlExam();
        try {
            String endpoint = "http://localhost:9001/axis/SqlExam.jws";            Service service = new Service();
            Call call = null;            call = (Call) service.createCall();            call.setOperationName(new QName(
                    "http://localhost:9001/axis/SqlExam.jws", "Sqlmain"));
            call.setTargetEndpointAddress(new java.net.URL(endpoint));            //ResultSet ret = (ResultSet) call.invoke(new Object[] {say});
    String ret = (String) call.invoke(new Object[] {say});
    //String ret = (ResultSet) call.invoke(endpoint,"");
            System.out.println(ret);
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}
运行结果如下：
学号: 1
姓名: 11出生日期: 2006-03-03数学: 11物理: 11英语: 11学号: 2
姓名: 22出生日期: 2006-03-03数学: 22物理: 22英语: 22学号: 3
姓名: 33出生日期: 2006-03-03数学: 33物理: 33英语: 33学号: 4
姓名: 44出生日期: 2006-03-03数学: 44物理: 44英语: 44学号: 5
姓名: 55出生日期: 2006-03-03数学: 55物理: 55英语: 55学号: 6
姓名: 66出生日期: 2006-03-03数学: 66物理: 66英语: 66- Exception:
AxisFault
 faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException
 faultSubcode:
 faultString: java.io.IOException: No serializer found for class SqlExam in regi
stry org.apache.axis.encoding.TypeMappingDelegate@11dba45
 faultActor:
 faultNode:
 faultDetail:
        {http://xml.apache.org/axis/}stackTrace:java.io.IOException: No serializ
er found for class SqlExam in registry org.apache.axis.encoding.TypeMappingDeleg
ate@11dba45
        at org.apache.axis.encoding.SerializationContext.serializeActual(Seriali
zationContext.java:1429)
        at org.apache.axis.encoding.SerializationContext.serialize(Serialization
Context.java:914)
        at org.apache.axis.encoding.SerializationContext.outputMultiRefs(Seriali
zationContext.java:989)
        at org.apache.axis.message.SOAPBody.outputImpl(SOAPBody.java:145)
        at org.apache.axis.message.SOAPEnvelope.outputImpl(SOAPEnvelope.java:477
)
        at org.apache.axis.message.MessageElement.output(MessageElement.java:120
8)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:315)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:269)
        at org.apache.axis.SOAPPart.saveChanges(SOAPPart.java:530)
        at org.apache.axis.attachments.AttachmentsImpl.getAttachmentCount(Attach
mentsImpl.java:519)
        at org.apache.axis.Message.getContentType(Message.java:475)
        at org.apache.axis.transport.http.HTTPSender.writeToSocket(HTTPSender.ja
va:343)
        at org.apache.axis.transport.http.HTTPSender.invoke(HTTPSender.java:138)        at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrateg
y.java:32)
        at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
        at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
        at org.apache.axis.client.AxisClient.invoke(AxisClient.java:165)
        at org.apache.axis.client.Call.invokeEngine(Call.java:2765)
        at org.apache.axis.client.Call.invoke(Call.java:2748)
        at org.apache.axis.client.Call.invoke(Call.java:2424)
        at org.apache.axis.client.Call.invoke(Call.java:2347)
        at org.apache.axis.client.Call.invoke(Call.java:1804)
        at Saysql.main(Saysql.java:26)        {http://xml.apache.org/axis/}hostname:dengyujava.io.IOException: No serializer found for class SqlExam in registry org.apach
e.axis.encoding.TypeMappingDelegate@11dba45
        at org.apache.axis.AxisFault.makeFault(AxisFault.java:101)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:317)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:269)
        at org.apache.axis.SOAPPart.saveChanges(SOAPPart.java:530)
        at org.apache.axis.attachments.AttachmentsImpl.getAttachmentCount(Attach
mentsImpl.java:519)
        at org.apache.axis.Message.getContentType(Message.java:475)
        at org.apache.axis.transport.http.HTTPSender.writeToSocket(HTTPSender.ja
va:343)
        at org.apache.axis.transport.http.HTTPSender.invoke(HTTPSender.java:138)        at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrateg
y.java:32)
        at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:118)
        at org.apache.axis.SimpleChain.invoke(SimpleChain.java:83)
        at org.apache.axis.client.AxisClient.invoke(AxisClient.java:165)
        at org.apache.axis.client.Call.invokeEngine(Call.java:2765)
        at org.apache.axis.client.Call.invoke(Call.java:2748)
        at org.apache.axis.client.Call.invoke(Call.java:2424)
        at org.apache.axis.client.Call.invoke(Call.java:2347)
        at org.apache.axis.client.Call.invoke(Call.java:1804)
        at Saysql.main(Saysql.java:26)
Caused by: java.io.IOException: No serializer found for class SqlExam in registr
y org.apache.axis.encoding.TypeMappingDelegate@11dba45
        at org.apache.axis.encoding.SerializationContext.serializeActual(Seriali
zationContext.java:1429)
        at org.apache.axis.encoding.SerializationContext.serialize(Serialization
Context.java:914)
        at org.apache.axis.encoding.SerializationContext.outputMultiRefs(Seriali
zationContext.java:989)
        at org.apache.axis.message.SOAPBody.outputImpl(SOAPBody.java:145)
        at org.apache.axis.message.SOAPEnvelope.outputImpl(SOAPEnvelope.java:477
)
        at org.apache.axis.message.MessageElement.output(MessageElement.java:120
8)
        at org.apache.axis.SOAPPart.writeTo(SOAPPart.java:315)
        ... 16 more
现在又陷入了郁闷之中！SOS中