Kigen's Anti-Cheat

Hey today i got this log but its showing a error
i think he wanted to open a script but nothing happened.

L 04/14/2010 - 16:29:07: Bad CVar return: 10hib0yz. kAVEN i; (ID: STEAM_0:1:24169734 | IP: 95.154.18.6) has convar "openscript_version" (value "", return Not valid) when it shouldn't exist.

That is that LUA Source Scripting thing. Its used to exploit and cheat on servers.

Kigen wrote:That is that LUA Source Scripting thing. Its used to exploit and cheat on servers.

But why it doest banned him ? I have every convar enabled except crashprevent and client balance.