WebServiceContext or handle to session in CXF JAX-RS implementation

[Mani Sound]

Hi
I'm using JAX-RS for implementing RESTful service. I'm trying to get hold of session. Over the articles, it is mentioned that we can get it from WebServiceContext in the following manner.
((HttpServletRequest)context.getMessageContext().get(MessageContext.SERVLET_REQUEST)).getSession()

Please find the implementation class, web.xml and spring-config.xml below. The problem is WebServiceContext is null. Can someone please tell me how to get a handle to session?

    
@Path("/cartservice/")
@ProduceMime("application/xml")
public class ShoppingCartServiceImpl
		implements ShoppingCartService
{
	@Resource
	private HttpServletRequest request;

	 @Resource
        public void setContext(WebServiceContext context) 
			{
				System.out.println("Setting the context..." + context );
				 this.request =(HttpServletRequest)context.getMessageContext().get(MessageContext.SERVLET_REQUEST); 
			     this.wsContext = context;
			}


		@POST
	    @Path("/addtocart")	
		public ShoppingCart addToCart (@Context MessageContext mc, @Context HttpHeaders h, @Context HttpServletRequest r, ShoppingCart webCart )
			{
				System.out.println("****WS context-->" + wsContext);
				MessageContext ctx = wsContext.getMessageContext();
				System.out.println("****Message Context frm ws context-->" + wsContext.getMessageContext());
				this.request.getSession().setAttribute("cart", webCart);
			...

This is my spring-config.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:jaxrs="http://cxf.apache.org/jaxrs"
  xsi:schemaLocation="
	http://www.springframework.org/schema/beans
	http://www.springframework.org/schema/beans/spring-beans.xsd
	http://cxf.apache.org/jaxrs
	http://cxf.apache.org/schemas/jaxrs.xsd">

  <import resource="classpath:META-INF/cxf/cxf.xml" />
  <import resource="classpath:META-INF/cxf/cxf-extension-jaxrs-binding.xml" />
  <import resource="classpath:META-INF/cxf/cxf-servlet.xml" />

  <jaxrs:server id="shoppingCartService" address="/">
    <jaxrs:serviceBeans>
      <ref bean="shoppingCartServiceBean" />
    </jaxrs:serviceBeans>
  </jaxrs:server>

  <bean id="shoppingCartServiceBean" class="com.poc.web.serviceimpl.ShoppingCartServiceImpl" >
  	<property name="wsContext" ref="contextBean" />
  </bean>
  
  <bean id="contextBean" class="org.apache.cxf.jaxws.context.WebServiceContextImpl">
  </bean> 
</beans>

This is my web.xml entry
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
	<display-name>
	poc</display-name>
	<welcome-file-list>
		<welcome-file>home.jsp</welcome-file>
	</welcome-file-list>
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>WEB-INF/spring-config.xml</param-value>
	</context-param>
	<listener>
		<listener-class>
			org.springframework.web.context.ContextLoaderListener
		</listener-class>
	</listener>	
	<servlet>
		<display-name>CXF Servlet</display-name>
		<servlet-name>CXFServlet</servlet-name>
		<servlet-class>
			org.apache.cxf.transport.servlet.CXFServlet
		</servlet-class>
		<load-on-startup>1</load-on-startup>
	</servlet>
	<servlet-mapping>
		<servlet-name>CXFServlet</servlet-name>
		<url-pattern>/*</url-pattern>
	</servlet-mapping>	
</web-app>