however, if you got it working you could become like super duper administrator stuff
like valves security thingy? vac?
basically, you log enough info to determine
a: how fast they leveled
b: who they are (blid, name, ip, time spent on which server)
c: logging almost everything
then you have hosts or players report people who they think are cheating somehow (joined a game at level 10000? yeaaahhhh)
once you've confirmed they're cheating.... permanently ban them from all servers running your mod. Do it via script and not the "banblid" command because you don't want them banned from the server, you want them banned from playing the mod.
this should work because
a: only a few smart individuals will be able to cheat (coders/clever noncoders) so the group of cheaters is sparse already
b: permanently loving banning people like loving hell
ANOTHER THING: have the client mod ask your server "hey, I joined this server at [ip]. are they legit?"
basically, if the players tamper with the game, bypassing bans, join messages, data syncronization, then your server will be all "well stuff something is up with that" and say to the client "no, something isn't right."
the client can then make a really annoying gui with bright red colors: "SERVER CRACKED, UNOFFICIAL BUILD" or "SERVER NOT AUTHENTICATED" or even better "HOST MAY BE CHEATING, DATA SYNC DISABLED."
you have client mods, server mods, and the server. have them all keep track of monies, have the client and server report to your server. if something doesn't match up, ignore it... you can't solidly tell who is cheating in that scenario, and you don't want to ban a client because the server is loving with him somehow
yeah this would be really difficult, and there isn't a way to automate it. however, you can do a number of things to mitigate it, as well as extensive data logging, as well as manual human moderation would lead to a pretty okay experience.