I have been banned from op pvp of "hacking" and i do not hack, i gotta be honest, i do have xray, but i do not use that for pvp because i dont find that very useful if in a 1v1, i do not have any other hack and idk but i have been banned from op pvp...i would very much like getting unbanned :P
Having a hack client on the server is not allowed. If you wish to be unbanned then you may make a ban appeal here: http://www.mineverse.com/forums/ban-appeals.87/