If you have not noticed it yet, it might be time to check out the Java DB download site for a refresh of a more stable and feature rich version of this Java-only DB! There has been lots of hard work and I've written about it earlier on this blog. (See below, for example, here. This refresh doesn't come with JDBC 4 APIs but watch for that as soon as the JDK 6 becomes generally available.)
I wrote a brief note on the early archeology of Shoal. However, for a more definitive commentary, you should consult Mohamed AbdelAziz's overview and Shreedhar Ganapathy's introduction.
Sit back, relax and watch the live web cast at http://sun.com/javanews on Monday, November 13 at 9:30 a.m. PST, for an important Java news!