In the bonus list on the character stats page the seconds are counted instead of the mana.
If there are 3 items with 4 mana per 5 seconds it displays a total Bonus of 4 mana per 15 seconds.
The item tooltip shows the seconds first and after that the mana amount.
eg. "Stellt alle 5 Sek. 4 Mana wieder her." The character stats seem to count the first value, wich produces incorrect results on german rosters.