I have performed some tests and I finally run successfully mpiexec without simlinks. As Thomas said my error was the LD_LIBRARY_PATH setting. The correct setup is the following:
source /home/stefano/opt/intel/2013.4.183/bin/compilervars.sh intel64
Using the above setting mpiexec (orted) finds all its shared library also with remote node runs. My previous setups were wrong because:
1) in the first test I have forgot /home/stefano/opt/intel/2013.4.183/lib in the LD_LIBRARY_PATH;
2) in the second test I have used /home/stefano/opt/intel/2013.4.183/lib/intel64 in the LD_LIBRARY_PATH.
It seems that the source of compilervars.sh does not set the correct LD_LIBRARY_PATH.
Thanks you for all suggestions,