Hi,
I was using 2.0.3 in weblogic 8.1 environment with no problems however when I upgraded to version 2.1.1 the initialisation never gets past the following line in the log -

net.sf.hibernate.cfg.SettingsFactory - Query language substitutions: {no='N', true=1, yes='Y', false=0}
net.sf.hibernate.cfg.SettingsFactory - cache provider: net.sf.hibernate.cache.HashtableCacheProvider
net.sf.hibernate.cfg.Configuration - instantiating and configuring caches

and it simply hangs at that point. The only changes I have made are to add the new cglib2.jar, ehcache.jar, jta.jar and Hibernate2.jar (I am using all the old required jar files that I used with 2.0.3) however I can

Actually,
I have found that net.sf.core.KeyFactory can't be found. I can't see why this is different to any of the other required hibernate libraries ???

Are you sure? I have never heard of such a class, is this really the classname? What class tries to load this? I am sure this is not a Hibernate dependency for 2.1.

the class is present in cglib2.jar but for some reason weblogic can't find it. The funny thing was that when I took the contents of the cglib2.jar file and dumped it into hibernate2.jar everything worked as it should !!

It is net.sf.cglib.core.KeyFactory - have you removed all old jar files?