Beamsplitting attack to the revised KKKP protocol and a possible   solution
  We show that the revised KKKP protocol proposed by Kye and Kim [Phys. Rev. Lett. 95,040501(2005)] is still insecure with coherent states by a type of beamsplitting attack. We then further revise the KKKP protocol so that it is secure under such type of beamsplitting attack. The revised scheme can be used for not-so-weak coherent state quantum key distribution. 
Xiang-Bin Wang, Qiang Zhang, Yu-Ao Chen, Wong-Young Hwang, Myungshik   Kim and Jian-Wei Pan