JSF Session timeout and auto redirect to login page without user intraction eventhough Ajax push is active

I'm using Iceface Icepush in my JSF application to send some notifications to client. Because of this session timeout never happen on my application.

I've specified session timeout 15 mins. My requirement is, server should invalidate session if there is no actual client interaction for 15 mins.

I did some search in iceface forum and added this context param in web.xml

<context-param>
    <param-name>org.icefaces.strictSessionTimeout</param-name>
    <param-value>true</param-value>
</context-param>

also someone has specified to use sessionTimeoutMonitor in faces-config.xml

<application>
 <resource-handler>org.icefaces.impl.application.SessionTimeoutMonitor</resource-handler>
</application>

But nothing works.

I wrote my own timeout monitor by extending the org.icefaces.impl.application.SessionTimeoutMonitor class and this works fine.

public class RWSessionTimeoutMonitor extends  SessionTimeoutMonitor{

private static Logger log = LoggerFactory.getLogger(RWSessionTimeoutMonitor.class);

public RWSessionTimeoutMonitor(ResourceHandler handler) {
    super(handler);
}

@Override
public boolean isResourceRequest(FacesContext context) {
    final ExternalContext externalContext = context.getExternalContext();
    //create session if non-ajax request
    final Object session = externalContext.getSession(!context.getPartialViewContext().isAjaxRequest());
    //if session invalid or expired block other resource handlers from running
    if (session == null) {
        //return false to force JSF to run and throw ViewExpiredException which eventually will be captured
        //and re-cast in a SessionExpiredException
        return false;
    }

    if (!EnvUtils.isStrictSessionTimeout(context)) {
        return getWrapped().isResourceRequest(context);
    }
    Map sessionMap = externalContext.getSessionMap();
    Long lastAccessTime = (Long) sessionMap.get(SessionTimeoutMonitor.class.getName());
    boolean isPushRelatedRequest = EnvUtils.isPushRequest(context);
    if (lastAccessTime == null || !isPushRelatedRequest) {
        lastAccessTime = System.currentTimeMillis();
        sessionMap.put(SessionTimeoutMonitor.class.getName(), System.currentTimeMillis());
    }

    int maxInactiveInterval;

    maxInactiveInterval = ((javax.servlet.http.HttpSession) session).getMaxInactiveInterval();

    if (System.currentTimeMillis() - lastAccessTime > maxInactiveInterval * 1000) {
        sessionMap.remove(SessionTimeoutMonitor.class.getName());
        externalContext.invalidateSession();
        log.info("No user request b/w max interval [{}], session is invalidated." , maxInactiveInterval );
    }

    return super.isResourceRequest(context);
}

}