XML Parsing Error: duplicate attribute for xmlns:xsd="http://www.w3.org/2001/XMLSchema"

I get XML Parsing Error: duplicate attribute for xmlns:xsd="http://www.w3.org/2001/XMLSchema". This attribute appears twice in the wsdl which ends up a failure in generating a proxy in the client side. I am using jax-ws with a pojo.

here is my code.

@WebService
public class HelloServiceImpl implements HelloService
{
public String echo(String input)

}

@WebService
public interface HelloService
{
public String echo(String input);
}

web.xml

<web-app>
<servlet>
<servlet-name>XFireServlet</servlet-name>
<display-name>XFire Servlet</display-name>
<servlet-class>
org.codehaus.xfire.transport.http.XFireConfigurableServlet
</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>XFireServlet</servlet-name>
<url-pattern>/servlet/XFireServlet/*</url-pattern>
</servlet-mapping>

<servlet-mapping>
<servlet-name>XFireServlet</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
</web-app>

services.xml

<!-- START SNIPPET: services -->
<beans xmlns="http://xfire.codehaus.org/config/1.0">
<service>
<name>HelloService</name>
<namespace>http://xfire.codehaus.org/HelloService</namespace>
<serviceClass>org.codehaus.xfire.demo.HelloService</serviceClass>
<serviceFactory>org.codehaus.xfire.annotations.AnnotationServiceFactory</serviceFactory>
</service>
</beans>

I don't know what the problem is. it seems like a parsing error.