Take a look at http://bugzilla.kernel.org/show_bug.cgi?id=3710
bugzilla tries to send a mail to the reporter, it fails ("unknown user account"),
but the error failure is appended as a bugzilla comment. Then bugzilla tries to
send that comment to everyone involved in the bug, including the reporter,
so it fails again.....Houston, we've a endless loop.
There're 540 comments in that bug report already, and the bugme-daemon
mail list is being spammed....
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