Rospack Error Eigen missing

edit

This is running on Ubuntu 12.04 in a virtualbox on windows7

I'm trying to make the hand_interaction package for kinect, but it won't compile.

Here's my error:

mkdir -p bin cd build && cmake -Wdev -DCMAKE_TOOLCHAIN_FILE=rospack find rosbuild/rostoolchain.cmake .. -- Eigen found (include: /usr/include/eigen3) [rosbuild] Building package hand_interaction
Failed to invoke /opt/ros/fuerte/bin/rospack deps-manifests hand_interaction
[rospack] Error: package/stack hand_interaction depends on non-existent package eigen

 CMake Error at /opt/ros/fuerte/share/ros/core/rosbuild/public.cmake:133

(message):

Failed to invoke rospack to get compile flags for package
'hand_interaction'.  Look above for errors from rospack itself.

Aborting. Please fix the broken dependency!

Thanks!