I just found this one on EBay, I have never heard of one of them before and have reservations about this one. If it is actually designed to include a 'hiding place" for spoils of war how would it work when the butt plate appears to be 'rivited ' to the wood rather than screws that could be removed to gain access to the hiding place. I also was not aware that the soldiers were watched so closely that they couldn't just put something small enough to fit in the hiding place in their pocket. Interesting piece though, I wonder if he has the x-rays to prove that it is hollow inside?
http://cgi.ebay.com/ws/eBayISAPI.dll...507671638&rd=1