what do you do?

My LO is 6 months and he is starting to explore things when I change his diaper.  I don't mind him doing this except when he poops.  I give him something to play with so he is distracted but he always knows when the diaper comes off.  He hasn't gotten it on his hands YET but he has gotten close to the poop on his bottom and I can't seem to wipe it fast enough before his hands are down there.  Any suggestions?