have used JBoss 4.0.2 Stateless Session bean with Hibernate 3.0.5
Unfortunately I have a problem with exchanging Value(or DTO) Objects retreive by Hibernate when they contain one-to-many or many-to-many relations ships and contain a Set of another Value Objects. When I want to retreive such objects by calling the EJB remotely I encountered following exception:

java.lang.reflect.UndeclaredThrowableException
    at $Proxy2.getUserProfile(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at org.springframework.remoting.rmi.RmiClientInterceptorUtils.doInvoke(RmiClientInterceptorUtils.java:98)
    at org.springframework.ejb.access.SimpleRemoteSlsbInvokerInterceptor.doInvoke(SimpleRemoteSlsbInvokerInterceptor.java:75)
    at org.springframework.ejb.access.AbstractRemoteSlsbInvokerInterceptor.invoke(AbstractRemoteSlsbInvokerInterceptor.java:114)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:174)
    at $Proxy1.getUserProfile(Unknown Source)
    at com.telexis.nsbpm.workflow.security.service.RemoteSecurityServiceTest.testGetUserProfile(RemoteSecurityServiceTest.java:72)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at com.intellij.rt.execution.junit2.JUnitStarter.main(JUnitStarter.java:31)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:78)
Caused by: java.io.InvalidClassException: org.hibernate.collection.AbstractPersistentCollection; local class incompatible: stream classdesc serialVersionUID = -6208749127098131726, local class serialVersionUID = -7982170513654570219
    at java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:519)
    at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1546)
    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1460)
    at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1546)
    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1460)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1693)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
    at java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:1912)
    at java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:1836)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1713)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1299)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:339)
    at java.rmi.MarshalledObject.get(MarshalledObject.java:135)
    at org.jboss.invocation.jrmp.interfaces.JRMPInvokerProxy.invoke(JRMPInvokerProxy.java:119)
    at org.jboss.invocation.InvokerInterceptor.invokeInvoker(InvokerInterceptor.java:227)
    at org.jboss.invocation.InvokerInterceptor.invoke(InvokerInterceptor.java:167)
    at org.jboss.proxy.TransactionInterceptor.invoke(TransactionInterceptor.java:46)
    at org.jboss.proxy.SecurityInterceptor.invoke(SecurityInterceptor.java:55)
    at org.jboss.proxy.ejb.StatelessSessionInterceptor.invoke(StatelessSessionInterceptor.java:97)
    at org.jboss.proxy.ClientContainer.invoke(ClientContainer.java:86)