jboss7.x - java.util.ConcurrentModificationException occurs during session replication -

i have been using vaadin without issues in single standalone jboss 7.1.3 environment. when running 2 jboss nodes in cluster session replication enabled, concurrentmodificationexception (see stacktrace below) occurs when session replication occurs. there 1 user on system @ time, , there no add-ons part of project starting separate thread. stacktrace below occurred on page contains table. however, problem can replicated on other page well.

i've had headache days trying figure out. have ideas or suggestions cause of this? assistance appreciated.

12:28:53,939 error [org.infinispan.interceptors.invocationcontextinterceptor] (ajp-/10.52.1.124:8009-4) ispn000136: execution error: org.infinispan.cacheexception: java.lang.runtimeexception: failure marshal argument(s)     @ org.infinispan.util.util.rewrapascacheexception(util.java:526) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.commandawarerpcdispatcher.invokeremotecommand(commandawarerpcdispatcher.java:172) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.jgroupstransport.invokeremotely(jgroupstransport.java:489) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.invokeremotely(rpcmanagerimpl.java:161) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.invokeremotely(rpcmanagerimpl.java:183) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.invokeremotely(rpcmanagerimpl.java:240) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.invokeremotely(rpcmanagerimpl.java:227) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.invokeremotely(rpcmanagerimpl.java:222) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.rpc.rpcmanagerimpl.broadcastrpccommand(rpcmanagerimpl.java:201) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.replicationinterceptor.broadcastprepare(replicationinterceptor.java:136) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.replicationinterceptor.visitpreparecommand(replicationinterceptor.java:128) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.handledefault(commandinterceptor.java:130) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.abstractvisitor.visitpreparecommand(abstractvisitor.java:126) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.handledefault(commandinterceptor.java:130) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.abstractvisitor.visitpreparecommand(abstractvisitor.java:126) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.entrywrappinginterceptor.visitpreparecommand(entrywrappinginterceptor.java:93) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.locking.abstracttxlockinginterceptor.invokenextandcommitif1pc(abstracttxlockinginterceptor.java:120) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.locking.optimisticlockinginterceptor.visitpreparecommand(optimisticlockinginterceptor.java:131) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.notificationinterceptor.visitpreparecommand(notificationinterceptor.java:58) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.txinterceptor.visitpreparecommand(txinterceptor.java:106) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.statetransferlockinterceptor.handlewithretries(statetransferlockinterceptor.java:213) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.statetransferlockinterceptor.visitpreparecommand(statetransferlockinterceptor.java:85) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.handledefault(commandinterceptor.java:130) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.abstractvisitor.visitpreparecommand(abstractvisitor.java:126) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.invocationcontextinterceptor.handleall(invocationcontextinterceptor.java:132) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.invocationcontextinterceptor.handledefault(invocationcontextinterceptor.java:91) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.abstractvisitor.visitpreparecommand(abstractvisitor.java:126) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.base.commandinterceptor.invokenextinterceptor(commandinterceptor.java:116) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.batchinginterceptor.handledefault(batchinginterceptor.java:86) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.abstractvisitor.visitpreparecommand(abstractvisitor.java:126) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.commands.tx.preparecommand.acceptvisitor(preparecommand.java:133) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.interceptors.interceptorchain.invoke(interceptorchain.java:345) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.transactioncoordinator.commit(transactioncoordinator.java:174) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.synchronization.synchronizationadapter.aftercompletion(synchronizationadapter.java:81) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.tm.dummytransaction.notifyaftercompletion(dummytransaction.java:285) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.tm.dummytransaction.runcommittx(dummytransaction.java:334) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.tm.dummytransaction.commit(dummytransaction.java:91) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.transaction.tm.dummybasetransactionmanager.commit(dummybasetransactionmanager.java:102) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.as.clustering.web.impl.transactionbatchingmanager.endbatch(transactionbatchingmanager.java:75)     @ org.jboss.as.web.session.distributablesessionmanager.processsessionrepl(distributablesessionmanager.java:1515) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.distributablesessionmanager.storesession(distributablesessionmanager.java:857) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.instantsnapshotmanager.snapshot(instantsnapshotmanager.java:47) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.clusteredsessionvalve.handlerequest(clusteredsessionvalve.java:142) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.clusteredsessionvalve.invoke(clusteredsessionvalve.java:99) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.jvmroutevalve.invoke(jvmroutevalve.java:92) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.session.lockingvalve.invoke(lockingvalve.java:64) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.jboss.as.web.security.securitycontextassociationvalve.invoke(securitycontextassociationvalve.java:165) [jboss-as-web-7.1.3.final.jar:7.1.3.final]     @ org.apache.catalina.core.standardhostvalve.invoke(standardhostvalve.java:155) [jbossweb-7.0.17.final.jar:]     @ org.apache.catalina.valves.errorreportvalve.invoke(errorreportvalve.java:102) [jbossweb-7.0.17.final.jar:]     @ org.apache.catalina.core.standardenginevalve.invoke(standardenginevalve.java:109) [jbossweb-7.0.17.final.jar:]     @ org.apache.catalina.connector.coyoteadapter.service(coyoteadapter.java:372) [jbossweb-7.0.17.final.jar:]     @ org.apache.coyote.ajp.ajpprocessor.process(ajpprocessor.java:505) [jbossweb-7.0.17.final.jar:]     @ org.apache.coyote.ajp.ajpprotocol$ajpconnectionhandler.process(ajpprotocol.java:453) [jbossweb-7.0.17.final.jar:]     @ org.apache.tomcat.util.net.jioendpoint$worker.run(jioendpoint.java:931) [jbossweb-7.0.17.final.jar:]     @ java.lang.thread.run(thread.java:722) [rt.jar:1.7.0_09] caused by: java.lang.runtimeexception: failure marshal argument(s)     @ org.infinispan.remoting.transport.jgroups.commandawarerpcdispatcher.marshallcall(commandawarerpcdispatcher.java:257) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.commandawarerpcdispatcher.processsinglecall(commandawarerpcdispatcher.java:274) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.commandawarerpcdispatcher.invokeremotecommand(commandawarerpcdispatcher.java:165) [infinispan-core-5.1.7.final.jar:5.1.7.final]     ... 72 more caused by: java.util.concurrentmodificationexception     @ java.util.hashmap$hashiterator.nextentry(hashmap.java:894) [rt.jar:1.7.0_09]     @ java.util.hashmap$keyiterator.next(hashmap.java:928) [rt.jar:1.7.0_09]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:604)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:679)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:585)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:679)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.riverobjectoutputstream.defaultwriteobject(riverobjectoutputstream.java:159)     @ com.vaadin.event.listenermethod.writeobject(listenermethod.java:90) [vaadin-6.8.6.jar:6.8.6]     @ sun.reflect.generatedmethodaccessor98.invoke(unknown source) [:1.7.0_09]     @ sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43) [rt.jar:1.7.0_09]     @ java.lang.reflect.method.invoke(method.java:601) [rt.jar:1.7.0_09]     @ org.jboss.marshalling.reflect.serializableclass.callwriteobject(serializableclass.java:188) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1007)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:585)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:680)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:585)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:679)     @ org.jboss.marshalling.river.rivermarshaller.dowritefields(rivermarshaller.java:1063)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:1019)     @ org.jboss.marshalling.river.rivermarshaller.dowriteserializableobject(rivermarshaller.java:998)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:885)     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:680)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.as.clustering.simplemarshalledvalue.getbytes(simplemarshalledvalue.java:85)     @ org.jboss.as.clustering.simplemarshalledvalue.writeexternal(simplemarshalledvalue.java:175)     @ org.jboss.as.clustering.infinispan.io.externalizableexternalizer.writeobject(externalizableexternalizer.java:46)     @ org.jboss.as.clustering.infinispan.io.externalizableexternalizer.writeobject(externalizableexternalizer.java:36)     @ org.infinispan.marshall.jboss.externalizertable$foreignexternalizeradapter.writeobject(externalizertable.java:450) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.atomic.putoperation$externalizer.writeobject(putoperation.java:80) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.atomic.putoperation$externalizer.writeobject(putoperation.java:76) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.jboss.externalizertable$externalizeradapter.writeobject(externalizertable.java:401) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.marshall.marshallutil.marshallcollection(marshallutil.java:48) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.linkedlistexternalizer.writeobject(linkedlistexternalizer.java:50) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.linkedlistexternalizer.writeobject(linkedlistexternalizer.java:45) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.jboss.externalizertable$externalizeradapter.writeobject(externalizertable.java:401) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.atomic.atomichashmapdelta$externalizer.writeobject(atomichashmapdelta.java:110) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.atomic.atomichashmapdelta$externalizer.writeobject(atomichashmapdelta.java:106) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.jboss.externalizertable$externalizeradapter.writeobject(externalizertable.java:401) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.marshall.exts.replicablecommandexternalizer.writecommandparameters(replicablecommandexternalizer.java:83) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.replicablecommandexternalizer.writeobject(replicablecommandexternalizer.java:70) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.replicablecommandexternalizer.writeobject(replicablecommandexternalizer.java:58) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.jboss.externalizertable$externalizeradapter.writeobject(externalizertable.java:401) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.marshall.exts.replicablecommandexternalizer.writecommandparameters(replicablecommandexternalizer.java:85) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.cacherpccommandexternalizer.marshallparameters(cacherpccommandexternalizer.java:124) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.cacherpccommandexternalizer.writeobject(cacherpccommandexternalizer.java:111) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.exts.cacherpccommandexternalizer.writeobject(cacherpccommandexternalizer.java:66) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.jboss.externalizertable$externalizeradapter.writeobject(externalizertable.java:401) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.jboss.marshalling.river.rivermarshaller.dowriteobject(rivermarshaller.java:145)     @ org.jboss.marshalling.abstractobjectoutput.writeobject(abstractobjectoutput.java:62) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.jboss.marshalling.abstractmarshaller.writeobject(abstractmarshaller.java:119) [jboss-marshalling-1.3.15.ga.jar:1.3.15.ga]     @ org.infinispan.marshall.jboss.abstractjbossmarshaller.objecttoobjectstream(abstractjbossmarshaller.java:96) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.versionawaremarshaller.objecttobuffer(versionawaremarshaller.java:90) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.abstractmarshaller.objecttobuffer(abstractmarshaller.java:64) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.marshall.abstractdelegatingmarshaller.objecttobuffer(abstractdelegatingmarshaller.java:109) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.marshalleradapter.objecttobuffer(marshalleradapter.java:45) [infinispan-core-5.1.7.final.jar:5.1.7.final]     @ org.infinispan.remoting.transport.jgroups.commandawarerpcdispatcher.marshallcall(commandawarerpcdispatcher.java:255) [infinispan-core-5.1.7.final.jar:5.1.7.final]     ... 74 more caused by: exception occurred:     in field changedselectedkeys     in field componenttoexpandratio     in field root     in field components     in field content     in field componenttoexpandratio     in field parent     in field target     in field listenerlist     in field eventrouter     in field parent     in field parent     in field idpaintablemap     in field repaintrequestlisteners     in field mainwindow     in field applicationtoajaxappmgrmap     in object java.util.hashmap@38046b36     in object org.jboss.as.clustering.simplemarshalledvalue@38046b36     in object org.infinispan.atomic.putoperation@4a3da462     in object java.util.linkedlist@1d3ef9f9     in object org.infinispan.atomic.atomichashmapdelta@3829a747     in object org.infinispan.commands.write.putkeyvaluecommand@b1b7df3a     in object org.infinispan.commands.tx.preparecommand@706ff234 

i not sure if helps, far know, recommended way implement clustering in vaadin applications 1 should use sticky sessions, means load balancer forwards requests client same server initial request happened.