"[rospack] Error: stack/package simulator_gazebo not found" with Gazebo in shadow-fixed

edit

As described also here, I currently get this warning everytime I start gazebo for groovy installed from the shadow-fixed repo (leading to crashes and ROS related stuff not working) :

[rospack] Error: stack/package simulator_gazebo not found

I'm on Ubuntu 12.04/AMD64 and have groovy, fuerte and drcsim installed from .debs. I use a clean groovy environment:

kohlbrecher@opstation:~$ env |grep ROS
ROS_ROOT=/opt/ros/groovy/share/ros
ROS_PACKAGE_PATH=/opt/ros/groovy/share:/opt/ros/groovy/stacks
ROS_MASTER_URI=http://localhost:11311
ROS_DISTRO=groovy
ROS_ETC_DIR=/opt/ros/groovy/etc/roslib

Also, "roscd simulator_gazebo" works just fine.

I'm not sure this is bug or some kind of peculiarity of my system setup. In any case, if anyone has any ideas, has run across this problem before or knows how to fix it, I'd like to read any suggestions. ;)

/edit: It was suggested that it has to do with the rospack cache, but even after completely deleting ~/.ros (so everything gets re-generated) the error persists.