I was a bit bored with my current project, and was looking over some of the work I did recently, and remembered that I ported PostgreSQL to Android a while ago. After gaining approval to make my work publicly available, I put it up on Google Code. So be sure to check out the PsqlDroid project page if you're interested.
There is still a considerable amount of work to be done to publish Java bindings in the Dalvik VM (probably with with the existing PostgreSQL JDBC driver).
Any help is appreciated!