Return primitive Wrapper types for jersey - Restful

One of the links i found

best practice to return primitive types

Right now, i have been stuggling to find a simple way to return a primitive type or its Wrapper class. Wrapper classes like Integer, Long are throwing RunTimeExceptions as they don't annotate @XmlRootElement

Exception thrown at runtime :

Apr 23, 2010 10:45:28 AM com.sun.jersey.server.impl.application.WebApplicationImpl initiate
INFO: Initiating Jersey application, version 'Jersey: 1.1.1-ea 07/14/2009 07:18 PM'
Apr 23, 2010 10:52:11 AM com.sun.jersey.spi.container.ContainerResponse write
SEVERE: A message body writer for Java type, class java.lang.Integer, and MIME media type, application/xml, was not found
Apr 23, 2010 10:52:11 AM com.sun.jersey.server.impl.application.WebApplicationImpl onException
SEVERE: Internal server error
javax.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:744)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:667)
	at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:658)
	at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:318)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:425)
	at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:604)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
	at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
	at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:390)
	at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
	at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
	at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
	at org.mortbay.jetty.Server.handle(Server.java:326)
	at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
	at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:924)
	at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)
	at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
	at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
	at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
	at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)

I want to know how could i return a Wrapper class like below :