IBM has donated Cloudscape, an embedded relational Java database that has been in active development since 1996, to the Apache project, where it will be called Apache Derby.
Can you guess on how fast Hibernate will come out with support for Cloudscape?
I haven't tried Hibernate yet. There's so much great open source database software for Java lately I can't keep up.
We've come a long way, thanks to the borglike might of the open source community. When I was writing one of the first versions of Teach Yourself Java in 21 Days, I couldn't find a free, good JDBC driver for Java anywhere.