LuaLua -- The question you asked implies that you would be illegally obtaining encrypted passwords to crack with the intention of compromising a system. I think that's why DjM was warning you to quickly rephrase that question to one that does not suggest illegal activities. Most folks here will not help you commit a crime.
If, however, you're interested in how to protect against such an attack, I would recommend using shadow passwords (mostly used these days anyway).
One more thing. The word 'telnet' makes the hairs back on my neck stand up. It's an antiquated and thoroughly insecure protocol. If you're not using ssh, you really should be!
