[Help] disconnected from server!

when ever i use the superknife hack, i always get an error saying dissonnected from server, is there some way to fix it?

i DLed it from

http://www.mpgh.net/forum/210-combat...per-knife.html

and, it works.. sound and all, i jsut get disconnected after like 5 sec. of using it... (playing on Elimination)
(running XP)

Super knife sux.