sleep() weaknesses

hi, I just uploaded paper about remote password guessing (and why sleep(x) is not enough to protect) with help of threads and other tricks. Its avail at www.cs.uni-potsdam.de/homepages/students/linuxer/tad.tar.gz It includes sample-program for high guessing-rates and a benchmark-server if you don't want (can) to use your ISP's pop3d. :) regards, Sebastian