lol man..have u ever use like cheatengine?when u open it the gameguard write u a message 'illegan program detected' something like this ...
with l2phx or hlapex u can log in but the problem is inside!the packets like this :1b 10 00 00 00 is blocked from the server
and if u send it it will detect you and you will be kicked or banned or jailed(setting from the server files)
as i know this is the problem! if i am wrong ,sorry ;)