Any chance of raising this a bit so we can have lots of members on? It seems to have replaced TS2 anyways.
Myself, Trax, and Haven have looked at this already - the problem seems to be that it was supposed to have generated some kind of special key/password so that we can give someone the elevated permissions required to change that setting - but we can't find it anywhere.
TS3 uses a vastly different permissions system to TS2 and unfortunately getting the maxclients changed is apparently not as simple as clicking a button (though it should be for the person with the right permissions - the problem is getting those permissions in the first place).
Haven knows it's an issue but hasn't gotten around to looking at it properly yet.
EDIT: Just found
this post on the TS3 forums which looks like exactly what we need to do - just need Haven to do it on the server so he can then change the maxclients