Alsooooo
I made a few zombie poses and a very rigid walk that just happens to fit a zombie. There's no sit or hover, but that's because I figure zombies do neither. The poses are sold individually or you can buy the preconfigured AO (uses ZHAO, so I called it the ZHAOMBIE... aren't I clever?). It's pretty cheap as I remember.
Try out the poses before you buy the AO in case you think they're pants.
Available only at the UNPOP Main location at MO Island. Use places search!