Comment 6 for bug 728371

So there's two distinct problems happening here. The first is fixed by the solution in comment #5. This may not be the proper solution, but it's functional for now.

The second is caused by upstart growing support to manage chroot jobs. The chroot job gets invoked in this case with mysqld.sock outside the chroot. This means that dpkg-reconfigure mythtv-database doesn't have access to it.