After setup cvmfs (geant4.cern.ch + sft.cern.ch)...

1. Setup gcc:
. /cvmfs/sft.cern.ch/lcg/external/gcc/4.6.2/x86_64-slc6/setup.sh

2. Setup Geant4:
source /cvmfs/geant4.cern.ch/geant4/9.6/x86_64-slc6-gcc46-opt/GNUmake-setup.sh


3. Additional packages (for vis?):

   libglu1-mesa-dev
   libxmu-dev
   libxp-dev
   lesstif2-dev
   libxi-dev
   libssl-dev

4. Testing

cp -r $G4INSTALL/examples/extended/electromagnetic/TestEm7/ .
cd TestEm7/
make

-------------------------------------------------------------------------------
problemy z kompilacja na ubuntu z systemem 64 bitowym zostaly rozwiazane przez Pana Chmure w nastepujacy sposob:
   instalacja  
         libxpm-dev
         gcc-multilib 

   dowiazania symboliczne

           sudo ln -s /usr/lib/x86_64-linux-gnu /usr/lib64
           sudo ln -s /usr/lib/libXm.so.2 /usr/lib/libXm.so.4
--------------------------------------------------------------------------------

cp vis.mac $HOME/geant4_workdir/bin/Linux-g++/


cd $HOME/geant4_workdir/bin/Linux-g++
./TestEm7

(new window appears... then put in the "Session": "/control/execute vis.mac" and wait...)

In case of problems lets us know 
- type of problem 
- linux distribution
- gcc version

We will post here solutions to help others.