From: Suresh Bathini <sbathini_at_gmail.com>
Date: Sat, 15 Aug 2009 10:04:16 -0700

Resource code snippet:
--------------------------------
@Path ("/customer")
public class CustomerResource {

    @GET
    @Produces ("application/xml")
    public Customer getAccount(@QueryParam("customerId") String custId)
throws Exception{
        Customer act = null;
        ....
        return act;
    }
}

Java class:
-----------
@XmlRootElement(name = "Customer", namespace ="http://foo.com")
public class Customer implements Serializable{
    public Customer(){}

    @XmlElement(name = "name", namespace ="http://foo.com")
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

    @XmlElement(name = "id", namespace ="http://foo.com")
    public String getId() {
        return id;
    }
    public void setId(String id) {
        this.id = id;
    }

    @XmlElement(name = "emailId", namespace ="http://foo.com")
    public String getEmailId() {
        return emailId;
    }
    public void setEmailId(String emailId) {
        this.emailId = emailId;
    }

    @XmlElement(name = "address", namespace ="http://foo.com")
    public String getAddress() {
        return address;
    }
    public void setAddress(String address) {
        this.address = address;
    }

    private String emailId;
    private String address;
    private String name;
    private String id;
}

I get following exception...
EVERE: A message body writer for Java type, class Customer_$$_javassist_0,
and MIME media type, application/xml, was not found
Aug 14, 2009 11:39:39 PM
com.sun.jersey.server.impl.application.WebApplicationImpl onEx
ception
SEVERE: Internal server errorjavax.ws.rs.WebApplicationException
        at
com.sun.jersey.spi.container.ContainerResponse.write(ContainerResponse.java:241)
        at
com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:693)
        at
com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:616)
        at
com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:607)
        at
com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:309)

Troubleshooting ideas?
Thanks.