I'm starting to think that those batch numbers aren't really indicating different dot codes. We're collecting all the codes we can find over at the Better Than Tomorrow blog:
http://blog.betterthantomorrow.com/2011/08/05/lego-minifigures-series-5-the-codes/
So far we have confirmed two different bump codes for the Gangster, and identical codes for the Boxer even with different "batch numbers".
All help in this code collecting is highly appreciated, of course!