i develop a app using struts2, spring 3.1, Jpa2 and Hibernate. From Spring i use transactions and IoC.
so, i have an ajax code block that calls for a struts2 action every second (this is happening for every user that is logged into application (simultaneous users are around 20-30 at a time)). this action name is PopupAction

public class PopupAction extends VActionBase implements ServletRequestAware  {

private static final long serialVersionUID = -293004532677112584L;
private iIntermedService intermedService;
private HttpServletRequest servletRequest;          

@Override
public String execute() {               

    Integer agentId = (Integer) session.get("USER_AGENT_ID");           
    Intermed iObj;
    try {
        iObj = intermedService.getIntermed(agentId,locationsString);
    } catch (Exception e) {
        logger.error("Cannot get Intermed!!! "+e.getMessage());     
        return ERROR;
    }

        return SUCCESS;
}

}

and then i have the service class :

@Transactional(readOnly=true)
public class IntermedServiceImpl extends GenericIService<Intermed, Integer> implements iIntermedService {
@Override
public Intermed getIntermed (int agentId,String queueIds) throws Exception {

    Intermed intermedObj = null;

    //TODO - find a better implementation for this queueIds parameter!!!!         
    try{            
            String sql = "SELECT i FROM bla bla bla.....)";            
            Query q = this.em.createQuery(sql);

            List<Intermed> iList = q.getResultList();

            if (iList.size() == 1){
                intermedObj = (Intermed) iList.get(0);             
                //get latest object from DB
                em.refresh(intermedObj);
            }           
        }catch(Exception e){
            e.printStackTrace();
            logger.error(e.getCause()+e.getMessage());
            throw e;
        }

    return intermedObj;
}

}

here is the spring configuration :

 <bean id="emfI" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
      <property name="dataSource" ref="inboundDS" />  
      <property name="persistenceUnitName" value="I2PU"/>  
      <!-- GlassFish load-time weaving setup -->
       <property name="loadTimeWeaver">
        <bean class="org.springframework.instrument.classloading.glassfish.GlassFishLoadTimeWeaver"/>
      </property>       
    </bean>

<tx:annotation-driven transaction-manager="txManagerI" />
<tx:advice id="txManagerInboundAdvice" transaction-manager="txManagerI">
    <tx:attributes>  
     <tx:method name="*" rollback-for="java.lang.Exception"/>
    </tx:attributes>
 </tx:advice>

I have names for transactionManager because i have 3 datasources and 3 transaction managers. the problem is that my glassfish logs are full of messages like these: -- removed in order to be able to add more recent logs --

So the cause is : Caused by: java.lang.IllegalStateException: Transaction not active. But i have no idea what can cause this.
Any help ?
thanks
Updates
So i have added to @Transactional annotation the transaction manager name that he has to use, but this still does not solved my problem. I have captured a log from the time that the transaction is created until i got that exception:

    2012-02-08T15:08:55.954+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractBeanFactory.java:245) - Returning cached instance of singleton bean 'txManagerVA'
2012-02-08T15:08:55.962+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:365) - Creating new transaction with name [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly; '',-java.lang.Exception
2012-02-08T15:08:55.967+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:368) - Opened new EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9] for JPA transaction
2012-02-08T15:08:55.976+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:400) - Exposing JPA transaction as JDBC transaction [org.springframework.orm.jpa.vendor.HibernateJpaDialect$HibernateConnectionHandle@725b979b]
2012-02-08T15:08:55.977+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.jdbc.datasource.ConnectionHolder@4fb57177] for key [com.sun.gjc.spi.jdbc40.DataSource40@75fa4851] to thread [thread-pool-1-80(80)]
2012-02-08T15:08:55.978+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.orm.jpa.EntityManagerHolder@112c6483] for key [org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean@47d4f12f] to thread [thread-pool-1-80(80)]
2012-02-08T15:08:55.979+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:272) - Initializing transaction synchronization
2012-02-08T15:08:55.980+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionAspectSupport.java:362) - Getting transaction for [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed]
2012-02-08T15:08:55.983+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (ExtendedEntityManagerCreator.java:423) - Starting resource local transaction on application-managed EntityManager [org.hibernate.ejb.EntityManagerImpl@46d002f4]
2012-02-08T15:08:55.984+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:193) - Bound value [org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization@797add43] for key [org.hibernate.ejb.EntityManagerImpl@46d002f4] to thread [thread-pool-1-80(80)]
2012-02-08T15:08:55.986+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (ExtendedEntityManagerCreator.java:400) - Joined local transaction
2012-02-08T15:08:55.991+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionAspectSupport.java:391) - Completing transaction for [xxx.vs.common.services.inbound.IntermedServiceImpl.getIntermed]
2012-02-08T15:08:55.992+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:922) - Triggering beforeCommit synchronization
2012-02-08T15:08:55.994+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:935) - Triggering beforeCompletion synchronization
2012-02-08T15:08:56.001+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization@797add43] for key [org.hibernate.ejb.EntityManagerImpl@46d002f4] from thread [thread-pool-1-80(80)]
2012-02-08T15:08:56.002+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:752) - Initiating transaction commit
2012-02-08T15:08:56.003+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:507) - Committing JPA transaction on EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9]
2012-02-08T15:08:56.008+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:948) - Triggering afterCommit synchronization
2012-02-08T15:08:56.010+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (AbstractPlatformTransactionManager.java:964) - Triggering afterCompletion synchronization
2012-02-08T15:08:56.011+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:331) - Clearing transaction synchronization
2012-02-08T15:08:56.012+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.orm.jpa.EntityManagerHolder@112c6483] for key [org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean@47d4f12f] from thread [thread-pool-1-80(80)]
2012-02-08T15:08:56.021+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (TransactionSynchronizationManager.java:243) - Removed value [org.springframework.jdbc.datasource.ConnectionHolder@4fb57177] for key [com.sun.gjc.spi.jdbc40.DataSource40@75fa4851] from thread [thread-pool-1-80(80)]
2012-02-08T15:08:56.021+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (JpaTransactionManager.java:593) - Closing JPA EntityManager [org.hibernate.ejb.EntityManagerImpl@edf83f9] after transaction
2012-02-08T15:08:56.022+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|DEBUG [thread-pool-1-80(80)] (EntityManagerFactoryUtils.java:343) - Closing JPA EntityManager
2012-02-08T15:08:56.023+0200|INFO||_ThreadID=184;_ThreadName=Thread-5;|ERROR [thread-pool-1-80(80)] (PopupAction.java:39) - Cannot get Intermed!!! Transaction not active; nested exception is java.lang.IllegalStateException: Transaction not active
2012-02-08T15:08:56.024+0200|SEVERE||_ThreadID=184;_ThreadName=Thread-5;|org.springframework.dao.InvalidDataAccessApiUsageException: Transaction not active; nested exception is java.lang.IllegalStateException: Transaction not active
    at org.springframework.orm.jpa.EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(EntityManagerFactoryUtils.java:298)
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:106)
    at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.convertException(ExtendedEntityManagerCreator.java:501)
    at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.afterCommit(ExtendedEntityManagerCreator.java:481)
    at org.springframework.transaction.support.TransactionSynchronizationUtils.invokeAfterCommit(TransactionSynchronizationUtils.java:133)
    at org.springframework.transaction.support.TransactionSynchronizationUtils.triggerAfterCommit(TransactionSynchronizationUtils.java:121)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.triggerAfterCommit(AbstractPlatformTransactionManager.java:950)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:796)
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:723)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:393)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:120)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
    at $Proxy325.getIntermed(Unknown Source)
    at xxx.vs.common.actions.PopupAction.execute(PopupAction.java:37)
    at sun.reflect.GeneratedMethodAccessor1581.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:616)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:453)
    at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:292)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:255)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:256)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:176)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:211)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:75)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:90)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:141)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:145)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:192)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:187)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at xxx.vs.common.utils.AuthenticationInterceptor.intercept(AuthenticationInterceptor.java:78)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at com.googlecode.sslplugin.interceptors.SSLInterceptor.intercept(SSLInterceptor.java:128)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:249)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:510)
    at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
    at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:256)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:217)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:279)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
    at org.apache.catalina

2012-02-08T15:08:56.024+0200|SEVERE||_ThreadID=184;_ThreadName=Thread-5;|.core.StandardHostValve.invoke(StandardHostValve.java:162)
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
    at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
    at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
    at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
    at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
    at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
    at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
    at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
    at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
    at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
    at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
    at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
    at java.lang.Thread.run(Thread.java:679)
Caused by: java.lang.IllegalStateException: Transaction not active
    at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:69)
    at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerSynchronization.afterCommit(ExtendedEntityManagerCreator.java:478)
    ... 93 more

so again..... any ideea ?