I think that's the old cheat detection for blending (what's used for smoke grenades) being disabled. Mildly ironic, with his name being H@zE and all. Was that on a GT server?
The standalone client doesn't even allow you to change that setting, so I don't know why he would be getting kicked. Either he was up to something or, as bain suggested, typing a certain command at the console that triggered the kick.