All credit for this mod goes to Chesko and the Blackwolf Backpacks team.
You need the v1.1 assets for this mod http://www.nexusmods.com/fallout3/mods/14994
I recommend that you pack the meshes and textures into a BSA with BSAopt. Name the BSA "BBBackpacks - Assets.bsa" without the quotes.
Delete the original esp from the mod, and use this esm instead.