Folks, I have two webapp contexts under tomcat, and I want them to use a common dao.

So I want to split out our hibernate classes and the hbms into their own jar file... like their own eclipse project... DAO. Then make my two webapps dependent on this DAO project.

Is this possible, or do I need to have the *.hbm.xml files physically exist in each web app?

That is to say, each webapp would have a dao.jar with the DAO classes and hbms in there.. will this work? Is there anything special I have to do for this.. reference the hbm files differently?

For this problem, you should look towards an application server, not just a web server. JBoss has good integration with Hibernate and Tomcat so it will be easy for you.

Basically you will need to deploy 3 applications : 2 webapps (each one in a WAR file) and one Hibernate service (containing your Hibernate beans and you .hbm.xml files). This way you will access a single SessionFactory through JNDI.

If you want to save yourself some configuration steps you can package the whole thing (2 webapps + 1 Hibernate service) in a single EAR. This will be easier to deploy.