You're currently not on the normal ban list which means that there are three possible reasons for you being banned. The first is that it was a player made poll on the server, those only last an hour or an admin banned you for less than an hour (those don't show up in the logs if I remember correctly).
The final reason would be that you have been flagged as using an autoblocker, please check and post in this thread if you have (which is the most likely reason if you still can't get onto the servers);
http://forum.c-rpg.net/index.php/topic,23841.60.htmlTenne.