Mutual information, bit error rate and security in W\'{o}jcik's scheme
  In this paper the correct calculations of the mutual information of the whole transmission, the quantum bit error rate (QBER) are presented. Mistakes of the general conclusions relative to the mutual information, the quantum bit error rate (QBER) and the security in W\'{o}jcik's paper [Phys. Rev. Lett. {\bf 90}, 157901(2003)] have been pointed out. 
Zhanjun Zhang