Defined in /home/build/jenkins/workspace/RockBootstrap19/FLAVOR/master/label/DebianUnstable/dev/autoproj/remotes/rock.base/base.osdeps as

eigen3:
    debian:
        default: libeigen3-dev
        6.0.4,squeeze: nonexistent
      ubuntu:
        10.04,10.10,11.04,11.10: nonexistent
        default: libeigen3-dev
      fedora: eigen3-devel