Well... I acknowledge that not everybody liked playing arcanum online, but others might be curious about it, and knowing of the troubles when playing from the main game i come with... GameRanger! Game ranger is a utility focused on playing online various games, it supports age of empires, call of duty, command and conquer, civilization, and ARCANUM! i actually have not played arcanum online, mainly by the lack of people having it, but it would be nice to give it a try, just for fun. GameRanger also offers a well ordered game list, chatrooms, and support for several games. you can download it 'ere http://www.gameranger.com [my name there is Werozzi by the way]
This thread might be of use to you. Don't know how it compares to GameRanger but still it may be worth a shot.