#10 - March 26, 2008, 4:40 a.m.
I don't have any information on why it's happening but it's a known and logged bug and is slated to be resolved in a future update. I don't see any indication that this can be resolved through a hotfix but it is still possible, so don't lose hope.
If anyone has any specific information, such as this only affecting Warlocks (I couldn't tell if that was serious) please feel free to post or reply to any threads already tracking this issue in the Bug Report forum.