  The research described in this abstract was initiated by discussions between
the author and Giovanni Di Crescenzo in Barcelona in early 2004. It was during
Advanced Course on Contemporary Cryptology that Di Crescenzo gave a course on
zero knowledge protocols (ZKP), see [1]. After that course we started to play
with unorthodox ideas for breaking ZKP, especially one based on graph
3-coloring. It was chosen for investigation because it is being considered as a
"benchmark" ZKP, see [2], [3]. At this point we briefly recall such a
protocol's description.
