ejb - EJB3.1 NotSerializableException -

i getting error , don't know how fix:

java.io.notserializableexception: com.procc.dao.ejb31_generated_alertfacade_intf_bean_ @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1180) @ java.io.objectoutputstream.defaultwritefields(objectoutputstream.java:1528) @ java.io.objectoutputstream.writeserialdata(objectoutputstream.java:1493) @ java.io.objectoutputstream.writeordinaryobject(objectoutputstream.java:1416) @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1174) @ java.io.objectoutputstream.writeobject(objectoutputstream.java:346) @ java.util.hashmap.writeobject(hashmap.java:1100) @ sun.reflect.nativemethodaccessorimpl.invoke0(native method) @ sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:57) @ sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43) @ java.lang.reflect.method.invoke(method.java:601) @ java.io.objectstreamclass.invokewriteobject(objectstreamclass.java:975) @ java.io.objectoutputstream.writeserialdata(objectoutputstream.java:1480) @ java.io.objectoutputstream.writeordinaryobject(objectoutputstream.java:1416) @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1174) @ java.io.objectoutputstream.defaultwritefields(objectoutputstream.java:1528) @ java.io.objectoutputstream.writeserialdata(objectoutputstream.java:1493) @ java.io.objectoutputstream.writeordinaryobject(objectoutputstream.java:1416) @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1174) @ java.io.objectoutputstream.writearray(objectoutputstream.java:1362) @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1170) @ java.io.objectoutputstream.writeobject(objectoutputstream.java:346) @ java.util.hashmap.writeobject(hashmap.java:1100) @ sun.reflect.nativemethodaccessorimpl.invoke0(native method) @ sun.reflect.nativemethodaccessorimpl.invoke(nativemethodaccessorimpl.java:57) @ sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43) @ java.lang.reflect.method.invoke(method.java:601) @ java.io.objectstreamclass.invokewriteobject(objectstreamclass.java:975) @ java.io.objectoutputstream.writeserialdata(objectoutputstream.java:1480) @ java.io.objectoutputstream.writeordinaryobject(objectoutputstream.java:1416) @ java.io.objectoutputstream.writeobject0(objectoutputstream.java:1174) @ java.io.objectoutputstream.writeobject(objectoutputstream.java:346) @ com.sun.faces.renderkit.clientsidestatehelper.dowritestate(clientsidestatehelper.java:325) @ com.sun.faces.renderkit.clientsidestatehelper.writestate(clientsidestatehelper.java:173) @ com.sun.faces.renderkit.responsestatemanagerimpl.writestate(responsestatemanagerimpl.java:122) @ com.sun.faces.application.statemanagerimpl.writestate(statemanagerimpl.java:166) @ com.sun.faces.application.view.writebehindstatewriter.flushtowriter(writebehindstatewriter.java:225) @ com.sun.faces.application.view.faceletviewhandlingstrategy.renderview(faceletviewhandlingstrategy.java:419) @ com.sun.faces.application.view.multiviewhandler.renderview(multiviewhandler.java:131) @ com.sun.faces.lifecycle.renderresponsephase.execute(renderresponsephase.java:121) @ com.sun.faces.lifecycle.phase.dophase(phase.java:101) @ com.sun.faces.lifecycle.lifecycleimpl.render(lifecycleimpl.java:139) @ javax.faces.webapp.facesservlet.service(facesservlet.java:594) @ org.apache.catalina.core.standardwrapper.service(standardwrapper.java:1550) @ org.apache.catalina.core.standardwrappervalve.invoke(standardwrappervalve.java:281) @ org.apache.catalina.core.standardcontextvalve.invoke(standardcontextvalve.java:175) @ org.apache.catalina.core.standardpipeline.doinvoke(standardpipeline.java:655) @ org.apache.catalina.core.standardpipeline.invoke(standardpipeline.java:595) @ org.apache.catalina.core.standardhostvalve.invoke(standardhostvalve.java:161) @ org.apache.catalina.connector.coyoteadapter.doservice(coyoteadapter.java:331) @ org.apache.catalina.connector.coyoteadapter.service(coyoteadapter.java:231) @ com.sun.enterprise.v3.services.impl.containermapper$adaptercallable.call(containermapper.java:317) @ com.sun.enterprise.v3.services.impl.containermapper.service(containermapper.java:195) @ com.sun.grizzly.http.processortask.invokeadapter(processortask.java:860) @ com.sun.grizzly.http.processortask.doprocess(processortask.java:757) @ com.sun.grizzly.http.processortask.process(processortask.java:1056) @ com.sun.grizzly.http.defaultprotocolfilter.execute(defaultprotocolfilter.java:229) @ com.sun.grizzly.defaultprotocolchain.executeprotocolfilter(defaultprotocolchain.java:137) @ com.sun.grizzly.defaultprotocolchain.execute(defaultprotocolchain.java:104) @ com.sun.grizzly.defaultprotocolchain.execute(defaultprotocolchain.java:90) @ com.sun.grizzly.http.httpprotocolchain.execute(httpprotocolchain.java:79) @ com.sun.grizzly.protocolchaincontexttask.docall(protocolchaincontexttask.java:54) @ com.sun.grizzly.selectionkeycontexttask.call(selectionkeycontexttask.java:59) @ com.sun.grizzly.contexttask.run(contexttask.java:71) @ com.sun.grizzly.util.abstractthreadpool$worker.dowork(abstractthreadpool.java:532) @ com.sun.grizzly.util.abstractthreadpool$worker.run(abstractthreadpool.java:513) @ java.lang.thread.run(thread.java:722)

this alertfacade:

@stateless public class alertfacade extends abstractfacade { @persistencecontext(unitname = "flams_pu") private entitymanager em;

@override protected entitymanager getentitymanager() {     return em; }  public alertfacade() {     super(alert.class); } } 

which use in jsf managed bean.

is ejb supposed serializable ? don't it. please help

i try , add class signature implements serializable. since it's marker interface, don't have implement method.