The module .info file is missing core's block module dependency.
Patch attached in comments.
But menu block module works with Panels. So it actually doesn't require the block module to be enabled.
Oh. However, it caused uninstallation problems if it was being used together with block module. Maybe some sanity checks at uninstall time would be enough. Can't remember the message, though. I have it in the work computer.
Ah! I see what you mean.
Automatically closed -- issue fixed for 2 weeks with no activity.
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