Rene Engelhard: You are great man. Thank you very much for your rapid and precious help! You were right! I had an openoffice corrupted file.After reinstalling the package "openoffice.org-core", everything started working fine.
So it seems package "openoffice.org-core" got corrupted (I don't know why, because all I did was an "aptitude full-upgrade").
Have a nice day and long live Debian and package mantainers like you. JJCale