+1 to making H2 the default. It is not included in the JDK so we can ship it with whatever version we want. As for JavaDB, I've yet to hear any good comment about it, large footprint and slow performance are cited instead. Its only advantage is probably the Apache license. On the other hand, H2 will certainly require a larger footprint to support isolation, probably on par with JavaDB. For unit tests, space is not as big a concern as time, so overall I prefer H2 over JavaDB. I believe we should switch in the SOA branch first, for consistency with the ESB test environment and to better address the recent concurrency concerns. Once that is in a stable shape, we can merge the changes to head. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4136464#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...