We just discovered that we have paid thousands in duplicates commissions due to an apparent bug with a commission schedule that has the same item listed twice.  This isn't possible from the UI, so it's got to be a bug.

Here is a screenshot of the schedule:
http://lh5.ggpht.com/_XqB3s-LIbd0/SbW4z1HoS9I/AAAAAAAABl8/U6kuZMHWzio/duplicate%20items%20on%20commission%20schedule.png

Here is a screenshot of the duplicate commissions:
http://lh6.ggpht.com/_XqB3s-LIbd0/SbW8cfO79gI/AAAAAAAABmE/6QB5Fn8NENg/s1280/duplicate%20commissions.png

I'm terribly afraid to zero out one of the two item lines on the schedule because I don't know which one is the "bad" one.  I can only imagine making a change and then the next time I authorize ALL the valid commissions are reversed and only the duplicate, erroneous ones are left.  I have a 50/50 shot at getting it right.