Thanks go to the following people (sorted by alphabet):

* Alexey Maximov
   - for finding return-value and shell limitation bugs
* #cLinux IRC channel on irc.freenode.org
   - for testing and debugging (those I mean should know ;-)
* Daniel Aubry
   - for reporting many hints
* John Lawless
   - A lot of patches and some very interesting discussions.
* Markus Meier
   - for finding a really simple solution for choosing the right backup to
     clone from: Make it independent of the interval, simply choose the last
     one created.