ForePoint, like I said - max-station-count really only limits number of clients that can register. If in your setup this limit is not reached, there definitely is something else that causes this. You can test it by simply disabling/enabling wireless interface - this would effectively be the same as changing max-station-count.
If limit is reached (and some client(s) are not allowed to connect), what happens next solely depends on client software - they can retry to connect a few times, search for another suitable AP, retry periodically, etc.