I'm feeling guilt we haven't released SDB under ASL. Thoughts that come to mind are:
Whether to provide to do it as maven only release (and source-release on /dist), no binary download.
Include any database someone has provided the code for on the understanding that we haven't tested it. To put it another way - ship it if it does not get in the way.
The testing of a release is the barrier that I see - an approach is to release with testing of the core and rapidly respond to reports with a new release. Having coverage of several DBs gets increasing time consuming.
Andy