>
> You can change environment variables through your launch file:
> http://www.ros.org/wiki/roslaunch/XML/env
>   
True, but shouldn't it be the default within a launch environment to 
keep the system-wide environment variables intact, so that a node 
behaves identically from the command line and in the launch file?

Otherwise, you would have to adjust the launch file in question on each 
machine to point to exactly the same PYTHONPATH as is already configured 
on the machine...


Cheers,
Armin

-- 
Armin Hornung                              Albert-Ludwigs-Universität
www.informatik.uni-freiburg.de/~hornunga   Dept. of Computer Science
HornungA@informatik.uni-freiburg.de        Humanoid Robots Lab
Tel.: +49 (0)761-203-8010                  Georges-Köhler-Allee 79
Fax : +49 (0)761-203-8007                  D-79110 Freiburg, Germany