Our repository at http://svn.collab.net/repos/svn has been seeing some nasty lossage ("unable to complete cache flush" or something -- Mike has more details, can add them to this issue). This repository uses Berkeley DB 4.0.14. In the meantime, we've had various reports from the field about corruption in the db/changes table using BDB 4.1.24 and 4.1.25. People at Sleepycat said that what we saw was explainable if someone had been accessing the repository while running recovery. Not all reporters think they were doing so, however. So the situation right now is: 1) Unexplained lockups with 4.0.14 on svn.collab.net. 2) Unexplained lockups of a different sort with 4.1.24/25, but it's not clear whether these are due to pilot error or not. I'm not sure we want to spend time debugging 4.0.14, when it's such an old release now. It would be better to just require 4.1.x, if we can establish that this is safe (when taken according to doctor's instructions!). This issue is for tracking the overall task of digging ourselves out of BDB lossitude; it may get a new summary if we agree that upgrading is the right course.