Modified ID-based cryptosystem using discrete logarithm problem (comment)

See ibid., vol.24, p.858-9 (1988). Laih and Lee recently proposed a modified version for Tsujii et al.´s ID-based cryptosystem using the discrete logarithm problem, and they concluded that their scheme was highly secure in a practical sense. Here the commenters point out that Laih and Lee´s result is wrong by showing that their scheme can be completely broken by (n+1) entities´ conspiracy with overwhelming probability, where n is the number of the TC´s secret information.