Have you looked at raidb? http://c-jdbc.objectweb.org. Narrow niche, but if it happens to be the one you are in, then it's an option. I took a quick look at the user's page, and both of them were using PostgreSQL.
I just love those Java guys. The world starts and ends with Java.How do you execute a psql script with that thing ? How do you actually use any non-java stuff with it ? The same features could be implemented in a connection pool like pgpool2...
