The latest rev of the EJB spec renamed EmbeddableSuperclass to MappedSuperclass. I am pretty sure the tools do not generate any EmbeddableSuperclass annotations, so you will need to migrate your code.
The second problem is a known bug in the Seam templates. I believe it has already been reported in JIRA.
I did the workaround for the second bug that I found from an earlier post about specifying the @DataModelSelector("dataModelList").
I ended up re-installing JBoss 4.0.4RC1 and I no longer get the EmbedableSuperclass error I was seeing in the stacktrace. So that worked out.
Now all I need to do is figure out how to change my datasource jndi lookup from DefaultDS to something useful and I'll be all set!
Thanks for the help,
- Cory
Note that the existing JIRA issue is here:
http://opensource2.atlassian.com/projects/hibernate/browse/HBX-591
Fixed in Hibernate Tools CVS