The only thing I saw was someone on e-bay was selling a case that you put the cam in and(I beleive metal )lock it in that. You lag the metal case to the tree, there for it cant be puled off the tree.Here is the link
http://cgi.ebay.com/Moultrie-Game-Spy-D40-Digital-Trail-Camera-Security-Box_W0QQitemZ130259702936QQcmdZViewItem?hash=item1 30259702936