BabuDB/Java:

* bugfix: external threads blocking on full insertion queues are now notified as soon as new space becomes available in the queue (see issue #24)
* bugfix: creating a checkpoint while manually shutting down a database no longer raises an IllegalMonitorStateException (see issue #25)

git-svn-id: https://babudb.googlecode.com/svn/trunk@591 d4c7dd96-b7b2-11dd-893d-d98698f66bbf