I'm currently using Hibernate 2.1.6 and Java 1.4.2.

Are there any problems with moving to Java 5.0?

(I'm also using MySQL 4.1.7)

I don't think so, but you should consider moving to Hibernate3, it works for sure :-)

Following exception is thrown when I try to deploy my EJB Jar bundle. It includes hiberanate jars in lib folder and all are listed in META-INF. hibernate.cfg.xml is in root of jar file. and contained specifically these entries:

Code:
<!-- Transaction API -->
<property name="transaction.factory_class">net.sf.hibernate.transaction.JTATransactionFactory
</property>
<property name="transaction.manager_lookup_class">
net.sf.hibernate.transaction.JBossTransactionManagerLookup
</property>



Following is the exception is thrown while deploying this package:

org.jboss.deployment.DeploymentException: No ClassLoaders found for: org.jboss.resource.connectionmanager.LocalTxConnectionManager; - nested throwable: (java.lang.ClassNotFoundException: No ClassLoaders found for: org.jboss.resource.connectionmanager.LocalTxConnectionManager)
at org.jboss.system.ServiceConfigurator.install(ServiceConfigurator.java:143)
at org.jboss.system.ServiceController.install(ServiceController.java:200)
at sun.reflect.GeneratedMethodAccessor44.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)