To prevent the problem of innocent people being unable to properly participate in arena due to having a matching IP history with another character of which they no longer share any connection, we are having character IP history reset every time a 5 TC or more purchase is made. This will have the benefit of preventing actual character abuse via constant sharing while allowing those who truly aren't sharing to put their money where their mouth is. Also to help prevent confusion, the arena message will specify which characters are having the IP conflict.
Unfortunately this solution does not help different people who are constantly forced to play on the same network. There is no way to distinguish them from actual account sharers.
The reasoning and discussion for this issue can be found here:
http://forums.nodiatis.com/forums/sh...d.php_p=203089
A minor rounding issue (<0.01%) has been fixed when crossing experience penalty thresholds.