Comment 195 for bug 283316

The difference between the two has been an udev change:

  https://launchpad.net/ubuntu/+source/udev/173-0ubuntu4

I don't fully understand the ramifications of that patch towards
picking up CD-ROM events, but all other package updates which went
into the 1107.1 build has anything remotely to do with CD handling.

So if it's confirmed that 1107 has that bug, but 1107.1 not, then most
likely that udev change magically fixed the problem.