Creating Person with attributes throws ConversionException

{
   "names": [{
           "givenName": "Saptarshi",
           "familyName":"Purkayastha"
    }],
   "gender":"M",
   "age": 30,
   "attributes":[{
           "attributeType":"8d871d18-c2cc-11de-8d13-0010c6dffd0f",
           "value": "happy"
   }]
}

{"error":{"message":"Unable to convert object into response content","code":"org.openmrs.module.webservices.rest.web.resource.impl.BaseDelegatingResource:579","detail":"org.openmrs.module.webservices.rest.web.response.ConversionException: activeAttributes on class org.openmrs.Person\r\n\tat org.openmrs.module.webservices.rest.web.resource.impl.BaseDelegatingResource.setProperty(BaseDelegatingResource.java:579)\r\n\tat org.openmrs.module.webservices.rest.web.resource.impl.BaseDelegatingResource.setConvertedProperties(BaseDelegatingResource.java:446)\r\n\tat org.openmrs.module.webservices.rest.web.resource.impl.DelegatingCrudResource.create(DelegatingCrudResource.java:93)\r\n\tat org.openmrs.module.webservices.rest.web.v1_0.controller.BaseCrudController.create(BaseCrudController.java:83)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)\r\n\tat sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)\r\n\tat sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)\r\n\tat java.lang.reflect.Method.invoke(Method.java:597)\r\n\tat org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)\r\n\tat org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426)\r\n\tat org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790)\r\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719)\r\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644)\r\n\tat org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:560)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:727)\r\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:820)\r\n\tat org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:487)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1093)\r\n\tat org.openmrs.module.web.filter.ForcePasswordChangeFilter.doFilter(ForcePasswordChangeFilter.java:65)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.openmrs.module.web.filter.ModuleFilterChain.doFilter(ModuleFilterChain.java:76)\r\n\tat org.openmrs.module.webservices.rest.web.filter.AuthorizationFilter.doFilter(AuthorizationFilter.java:100)\r\n\tat org.openmrs.module.web.filter.ModuleFilterChain.doFilter(ModuleFilterChain.java:74)\r\n\tat org.springframework.web.filter.ShallowEtagHeaderFilter.doFilterInternal(ShallowEtagHeaderFilter.java:58)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)\r\n\tat org.openmrs.module.web.filter.ModuleFilterChain.doFilter(ModuleFilterChain.java:74)\r\n\tat org.openmrs.module.web.filter.ModuleFilter.doFilter(ModuleFilter.java:58)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.openmrs.web.filter.OpenmrsFilter.doFilterInternal(OpenmrsFilter.java:111)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:198)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.openmrs.web.filter.StartupFilter.doFilter(StartupFilter.java:109)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.openmrs.web.filter.StartupFilter.doFilter(StartupFilter.java:109)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.openmrs.web.filter.StartupFilter.doFilter(StartupFilter.java:109)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)\r\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)\r\n\tat org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1084)\r\n\tat org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:360)\r\n\tat org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)\r\n\tat org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:181)\r\n\tat org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:726)\r\n\tat org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:405)\r\n\tat org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:206)\r\n\tat org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)\r\n\tat org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)\r\n\tat org.mortbay.jetty.Server.handle(Server.java:324)\r\n\tat org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:505)\r\n\tat org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:843)\r\n\tat org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:648)\r\n\tat org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:211)\r\n\tat org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:380)\r\n\tat org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:395)\r\n\tat org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:488)\r\nCaused by: java.lang.NullPointerException\r\n\tat org.openmrs.module.webservices.rest.web.resource.impl.BaseDelegatingResource.setProperty(BaseDelegatingResource.java:561)\r\n\t... 59 more\r\n"}}