Problems with the model implementation

Hi all, 
I'm hoping you can offer some insight into my problem. I'm running keel2.1
and going through the 2.1 Hand's On tutorial and getting stuck at the first
part. I get Tomcat to startup, but as soon as I try to access
<http://localhost:8080/struts/model.do?model=createdb>, I get the following
error. 
<<< begin error >>> 
SEVERE: Stack for error 'Exception during model execution' (null, Could not
return a reference to the Component
(Key='org.keel.services.persist.PersistentFactory/*')) 
<<< end error >>> 
If I try to access <http://localhost:8080/struts/model.do?model=app.hoj>, I
get the following error 
<<< begin error >>> 
SEVERE: No elements in response from server
May 24, 2004 4:07:24 PM org.keel.clients.struts.StrutsClientConnector
handleErrors
SEVERE: Stack for error 'model' (Could not run model 'app.hoj' for role
'org.keel.services.model.Model', null, Unable to provide implementation for
org.keel.services.model.Model/app.hoj
(Key='org.keel.services.model.Model/app.hoj'))
org.keel.services.model.ModelException: Could not run model 'app.hoj' for
role 'org.keel.services.model.Model', null, Unable to provide implementation
for org.keel.services.model.Model/app.hoj
(Key='org.keel.services.model.Model/app.hoj') 
<<< end error >>> 
I can get to the home page fine (<http://localhost:8080/struts>). 
Any help would be greatly appreciated! 
Thanks, 
Anne